KR102121652B1 - An Orifice Type Timing Apparatus of Variable Valve for Engine - Google Patents

Abstract

The present invention relates to an orifice-type timing device for a variable valve for an engine capable of adjusting a sealing timing of an intake valve of an engine, and in particular, opening and closing of a flow path by adjusting a gap between a stem linearly moved by a motor and a housing surrounding the stem. It is configured to control the.
The present invention for achieving the above object is mounted on a push rod connecting a cam and a rocker arm that is rotated by the engine and controls the flow of the working oil flowing along the circulation path formed therein to power from the cam to the rocker arm. As a timing device for a variable valve for an engine that controls the timing to be transmitted, the upper plunger and the lower plunger which move up and down by a cam are located, and a chamber filled with hydraulic fluid therein, and as the upper plunger and lower plunger move upward, A circulating flow path connecting the upper and lower portions of the chamber so that the working fluid located at the bottom flows toward the upper portion of the chamber, and is mounted inside the circulating flow path, and moves along the circulating flow path to close or circulate the circulating flow path by contacting the inner circumferential surface of the circulating flow path Technical features include a stem that opens by forming an orifice between the inner circumferential surface of the flow path and a motor that generates power to move the stem.

Description

An Orifice Type Timing Apparatus of Variable Valve for Engine}

The present invention relates to an orifice-type timing device for a variable valve for an engine capable of adjusting a sealing timing of an intake valve of an engine, and in particular, opening and closing of a flow path by adjusting a gap between a stem linearly moved by a motor and a housing surrounding the stem. It is configured to control the.

In general, an engine is a device that converts thermal energy generated during combustion of fuel into mechanical energy. That is, the engine is a device that generates propulsive force on a vehicle, such as a ship, a vehicle. In such an engine, a plurality of cylinders are installed on the engine block, and an intake valve and an exhaust valve are installed in each cylinder. The intake valve and exhaust valve open or close the cylinder through a rocker arm, push rod, swing arm, or cam.

Meanwhile, in recent years, as the demand for eco-friendly high-efficiency engines has increased, research into improving the performance of various engines has been actively conducted. In particular, since the optimal intake or exhaust conditions have a great influence on improving engine performance, techniques for optimizing the opening and closing timing of the intake valves and exhaust valves in the engine through different valve timing adjustments according to the engine speed have been studied. .

The variable valve timing device of the engine is to increase the thermal efficiency, reduce smoke, and improve fuel efficiency by adjusting the opening and closing timing of the intake and exhaust valves according to conditions such as engine speed and load.

The variable valve timing device according to the prior art changes the phase of the cam to advance or delay the timing at which the intake valve closes the cylinder. Accordingly, the variable valve timing device according to the prior art has the following problems.

First, the variable valve timing device according to the prior art is not only impossible to adjust the closing timing of the intake valve unless the cam is changed, and it is not possible to actively control the closing timing, so it is impossible to optimize the valve timing according to the engine load. there is a problem.

Second, the variable valve timing device according to the prior art cannot adjust the valve timing according to the load of the engine, so the engine has low thermal efficiency and thus has poor fuel efficiency and increases the emission of nitrogen oxides (NOx) to pollute the environment. have.

In the drawing, FIG. 1 is a cross-sectional view showing a variable valve timing device of an engine according to the prior art, FIG. 2 is a detailed view showing the opening and closing portion shown in FIG. 1, and FIG. 3 is a stem of the opening and closing portion shown in FIG. It is a cross-sectional view showing a state where the circulation flow path is opened.

According to the technical content of the Republic of Korea Patent Publication No. 10-2017-0121766 (invention name; variable valve timing device for engines) for solving this problem, as shown in Figure 1, installed in the engine and inside The main body (2) providing a predetermined space, the upper plunger (3) which is installed to be elevated on the upper side of the main body (2), and the lower part installed on the lower side of the upper plunger (3) and the upper plunger (3) The plunger 4, the chamber 5 through which the hydraulic fluid flows as the upper plunger 3 moves up, and is installed on the outer periphery of the chamber 5 and connects the lower portion of the chamber 5 and the upper portion of the chamber 5 A circulation turn 6 and a logic turn valve 7 installed in the chamber 5 and communicating or blocking the upper portion of the chamber 5 and the lower portion of the chamber 5 as the upper plunger 3 moves up and down, The opening and closing part 8 for opening and closing the circulation flow passage 6 and the control unit for controlling the opening and closing part 8 so as to be installed in the circulation flow passage 6 and the lower part of the chamber 5 and the upper part of the chamber 5 communicate or block. (10) and a control unit 10 and includes a sensor unit 9 for measuring the load of the engine, and the control unit 10 is a circulation path 6 according to the load of the engine measured by the sensor unit 9 It characterized in that the opening and closing portion 8 is controlled to be opened and closed.

On the other hand, as shown in Figure 2, Republic of Korea Patent Publication No. 10-2017-0121766 described in the opening and closing portion 8 is a solenoid valve (Solenoid Valve) that operates according to the signal of the control unit 10, the opening and closing portion 8 ) The head 8F formed around the stem 8S and the stem 8S inserted into the housing 2H formed in the body 2 are moved in the front-rear direction so that they are in contact with or spaced apart from the head 8F. The step 2S formed on the inner circumferential surface of (2H), the inlet 6I of the circulation flow path 6 formed on the tip side of the housing 2H based on the step 2S and the head 8F, and the step 2S It includes the discharge port 6E of the circulation flow path 6 formed on the rear end side of the housing 2H based on the head 8F, and the head 8F and the step 2S of the stem 8S are in contact with each other in contact with each other. It characterized in that the inclined surfaces (8P, 2P) are formed respectively.

In the case of the variable valve timing device for an engine of the Republic of Korea Patent Publication No. 10-2017-0121766 configured as described above, the operation of the solenoid valve causes the stem 8S to move in the front-rear direction, and the head 8F formed on the stem 8S When the inclined surface 8P of the) and the inclined surface 2P formed in the step 2S of the housing 2H are in contact, the circulation flow path 6 is closed, and the working oil cannot flow along the circulation flow path 6, but in FIG. 3 As shown, when the gap between the inclined surface 8P of the head 8F formed in the stem 8S and the inclined surface 2P formed in the step 2S of the housing 2H when the stem 8S is reversed is formed The circulation flow path 6 is opened to circulate the working oil along the circulation flow path 6.

However, in the variable valve timing device for an engine configured as described above, as the stem moves in the front-rear direction and the head of the stem strikes the step of the housing, wear occurs on the contact surface or impacts the solenoid valve itself. This is applied, resulting in a disadvantage of poor durability. That is, when the valve is used for a long time, although the opening and closing portion closes the circulating flow path, the working oil circulates along the circulating flow path due to abrasion, making it difficult to control the timing of the variable valve, and there is also a problem that durability of the opening and closing portion is deteriorated due to impact.

Republic of Korea Patent Publication No. 10-2017-0121766 (published date; 2017.11.03)

The present invention was invented to solve the problems of the prior art as described above, orifice-type timing of a variable valve for an engine having a structure capable of increasing the reliability of opening and closing without generating an impact when opening or closing a circulation flow path. The purpose is to provide a device.

The present invention for achieving the above object is mounted on a push rod connecting a cam and a rocker arm that is rotated by the engine and controls the flow of the working oil flowing along the circulation path formed therein to power from the cam to the rocker arm. As a timing device for a variable valve for an engine that controls the timing to be transmitted, the upper plunger and the lower plunger which move up and down by a cam are located, and a chamber filled with hydraulic fluid therein, and as the upper plunger and lower plunger move upward, A circulating flow path connecting the upper and lower portions of the chamber so that the working fluid located at the bottom flows toward the upper portion of the chamber, and is mounted inside the circulating flow path, and moves along the circulating flow path to close or circulate the circulating flow path by contacting the inner circumferential surface of the circulating flow path Technical features include a stem that opens by forming an orifice between the inner circumferential surface of the flow path and a motor that generates power to move the stem.

In addition, according to a preferred embodiment of the present invention, the stem located in the circulation passage formed in the body of the orifice type timing device is connected, and the thread shaft fastened to the body to convert the rotation of the motor into a linear reciprocating motion of the stem, and the circulation passage It is located inside and includes a housing for guiding the linear reciprocating motion of the stem with the stem accommodated therein, and a circulation flow path extending from the bottom of the chamber to the top of the chamber penetrates the housing and is formed inside the housing.

In addition, according to a preferred embodiment of the present invention, in the middle of the length of the housing, an inflow through hole is formed so that the hydraulic oil introduced from the bottom of the chamber flows into the housing, and the hydraulic oil inside the housing is discharged to the top of the chamber at the tip of the housing. A discharge through hole is formed, and a step is formed between the discharge through hole and the inlet through hole in a structure in which the tip of the housing in which the discharge through hole is formed is expanded than the middle of the length of the housing in which the inlet through hole is formed.

In addition, according to a preferred embodiment of the present invention, the head is formed on the stem, the outer circumferential surface of the head contacts the middle inner circumferential surface of the housing to block the flow of hydraulic oil, and the orifice is formed while the head of the stem moves to the expanded region .

In addition, according to a preferred embodiment of the present invention, the circulating flow path is formed from the inlet formed in the lower portion of the chamber, the inlet pipe extending to the inlet through hole of the housing, the outlet formed in the upper portion of the chamber, and from the outlet through hole in the housing to the outlet. It includes an extended discharge pipe.

As described above, the orifice-type timing device for the variable valve for an engine according to the present invention opens and closes the circulation passage while adjusting the clearance between the stem and the housing while the stem of the opening/closing part for opening and closing the circulation passage slides in the housing. Therefore, there is an advantage in that the operation reliability of the opening/closing portion can be increased by fundamentally blocking the occurrence of an impact applied while the stem moves as in the prior art.

In addition, the opening and closing portion of the conventional timing device is worn by the contact surface by impact, and if the wear occurs, even if the circulation passage is closed, leakage occurs and the reliability of the timing device is deteriorated, but the orifice type timing device of the engine variable valve according to the present invention Has the advantage of excellent reliability and durability because no wear occurs as the spacing of the orifice is adjusted.

1 is a cross-sectional view showing a variable valve timing device of an engine according to the prior art,
FIG. 2 is a detailed view showing the opening and closing unit shown in FIG. 1.
3 is a cross-sectional view showing a state in which the stem of the opening/closing portion shown in FIG. 2 is reversed to open a circulation flow path.
4 is a conceptual diagram of an engine in which an orifice type timing device for a variable valve for an engine according to the present invention is installed,
5 is a cross-sectional view of an orifice type timing device for a variable valve for an engine according to the present invention,
FIG. 6 is a detailed view of part'A' shown in FIG. 5.
7 is a cross-sectional view showing a state in which the upper plunger and the lower plunger move upward while the circulation flow path is closed,
8 is a cross-sectional view showing a state in which the lower plunger moves downward while the circulation flow path is closed,
9 is a cross-sectional view showing the flow relationship of the working oil in a state where the circulation flow path is opened.
10 is a simulation result graph showing the effect of closing the intake valve according to the opening degree of the variable orifice controlled by the stepping motor.

Hereinafter, a preferred embodiment of an orifice type timing device for an engine variable valve according to the present invention will be described in detail with reference to the accompanying drawings.

In the drawing, FIG. 4 is a conceptual diagram of an engine in which an orifice-type timing device for an engine variable valve according to the present invention is installed, FIG. 5 is a cross-sectional view of an orifice-type timing device in an engine variable valve according to the present invention, and FIG. It is a detailed view of the'A' portion shown in 5. And Figure 7 is a cross-sectional view showing a state in which the upper plunger and the lower plunger moved upward while the circulation flow path is closed, and FIG. 8 is a cross-sectional view showing a state in which the lower plunger moves downward in the closed flow path, 9 is a cross-sectional view showing the flow relationship of the working oil in a state where the circulation flow path is opened. Also, FIG. 10 is a simulation result graph showing the effect of the intake valve closing timing according to the degree of opening of the variable orifice controlled by the stepping motor.

4 to 6, the orifice-type timing device of the variable valve for an engine according to the present invention is for adjusting the timing at which the intake valve closes the combustion chamber according to the load of the engine. The combustion chamber is a closed space in which fuel and air are mixed and burned.

To this end, the orifice-type timing device 100 of the variable valve for an engine according to the present invention includes a main body 110, an upper plunger 113, a lower plunger 114, a chamber 115, a circulation passage 130, a logic turn It includes a valve 140, an opening/closing part 120, a sensor part 118, and a control part 119.

The orifice-type timing device 100 of the variable valve for an engine according to the present invention is installed between the swing arm 102 and the push rod 103. The push rod 103 is connected to the intake and exhaust valves 106 through a rocker arm 105.

The swing arm 102 may move up and down in conjunction with the cam 101 to elevate the orifice type timing device 100 of the engine variable valve. In this case, the lower plunger 114 may be moved up and down by the cam 101.

When the lower plunger 114 rises upward, the lower plunger 114 may move upward by pressing the upper plunger 113. At this time, the upper plunger 113 may press the push rod 103 to operate the intake and exhaust valves 106 through the rocker arm 105. In the detailed description according to the present invention, a case in which an orifice type timing device of an engine variable valve operates an intake valve will be described as an example.

The intake valve 106 may allow air to be injected into the combustion chamber by opening the combustion chamber. The intake valve 106 may block air injected into the combustion chamber by closing the combustion chamber. The amount of air supplied to the combustion chamber may vary according to the timing at which the intake valve 106 closes the combustion chamber. For example, when the timing at which the intake valve 106 closes the combustion chamber is fast, the amount of air injected into the combustion chamber may be less than when the timing at which the combustion chamber is closed is slow. Conversely, if the timing at which the intake valve 106 closes the combustion chamber is slow, the amount of air injected into the combustion chamber may be larger than when the timing at which the combustion chamber is closed is fast.

Hereinafter, the main body 110, the upper plunger 113, the lower plunger 114, the chamber 115, the circulation flow path 130, the logic turn valve 140, the opening and closing portion 120, the sensor portion 118 and the control unit ( 119) will be described in detail with reference to the accompanying drawings.

5 to 9, the main body 110 is formed to have a predetermined length. The body 110 is installed in the engine and provides a certain space therein. An upper plunger 113, a lower plunger 114, a chamber 115, and a logic turn valve 140 may be installed inside the body 110.

The upper plunger 113 is installed to be elevated on the upper side of the main body 110. The upper plunger 113 may have one side connected to the push rod 103 and the other side connected to the lower plunger 114. The upper plunger 113 may be raised by the lower plunger 114. In this case, the upper plunger 113 may raise the push rod 103 to operate the intake valve 106 through the rocker arm 105. Accordingly, the intake valve 106 may open the combustion chamber so that air is injected into the combustion chamber.

When the lower plunger 114 descends, the upper plunger 113 may descend together in a state in contact with the lower plunger 114 or slowly descend in a state separated from the lower plunger 114. In this case, the upper plunger 113 may lower the push rod 103 so that the intake valve 106 seals the combustion chamber. When the upper plunger 113 descends with the lower plunger 114, the timing for closing the combustion chamber can be advanced. When the upper plunger 113 slowly descends from the lower plunger 114, the timing for closing the combustion chamber may be delayed.

The upper plunger 113 may be formed in a'T' shape. The upper plunger 113 may include a head portion formed on the upper end and a body portion having a smaller diameter than the head portion. The body part may be inserted into a guide mechanism located under the head part and installed in the body 110. The guide 142 is for guiding the upper plunger 113 when the upper plunger 113 moves up and down.

The lower plunger 114 is installed under the upper plunger 113 and is intended to elevate the upper plunger 113.

The lower plunger 114 may raise and lower the upper plunger 113 in conjunction with the operation of the swing arm 102. The upper surface of the lower plunger 114 may contact the lower surface of the upper plunger 113. The lower plunger 114 may be moved in an upward direction as the swing arm 102 is raised to raise the upper plunger 113. The lower plunger 114 may move in a downward direction as the swing arm 102 descends, thereby lowering the upper plunger 113.

The chamber 115 is installed inside the main body 110. The upper plunger 113 may be installed in the chamber 115 to be elevated. The chamber 115 may include an upper portion formed on an upper side of the upper plunger 113 and a lower portion formed on a lower side of the upper plunger 113. The upper and lower portions of the chamber 115 may be communicated or blocked through the circulation passage 130 installed in the outer circumference of the chamber 115. The chamber 115 may be filled with hydraulic oil. The hydraulic oil may reduce friction generated between the chamber 115 and the upper plunger 113 and between the chamber 115 and the lower plunger 114. When the upper plunger 113 descends, the hydraulic oil may function to delay the descending of the upper plunger 113.

A logic turn valve 140 may be installed between the upper portion of the chamber 115 and the lower portion of the chamber 115.

As illustrated in FIG. 7, in the chamber 115, hydraulic oil may flow as the upper plunger 113 moves up and down. For example, when the circulation flow path 130 is blocked, when the upper plunger 113 is raised by the lower plunger 114, as the upper pressure of the chamber 115 increases, the hydraulic fluid is a logic turn valve inside the chamber 115 It may flow to the lower portion of the chamber 115 through (140). In this case, the lower pressure of the chamber 115 may be increased. 8, when the lower plunger 114 is lowered by the swing arm 102, the upper plunger 113 is separated from the lower plunger 114 and the upper plunger 113 and the lower plunger ( 114) may be filled with hydraulic oil. In this case, since the lower plunger 114 is directly connected to the swing arm 102, it can be directly lowered by the lowering of the swing arm 102, but the upper plunger 113 is hydraulic fluid filled between the lower plunger 114. Due to this, the descending speed may be slower than that of the lower plunger 114. That is, the fall time of the upper plunger 113 may be delayed compared to the lower plunger 114.

For example, as illustrated in FIG. 9, when the lower plunger 114 is lowered when the circulation flow path 130 is opened, the hydraulic oil is discharged from the lower portion of the chamber 115 and the hydraulic oil is supplied to the upper portion of the chamber 115. When the lower plunger 114 is lowered, the upper plunger 113 may descend together in a state in contact with the lower plunger 114 or may descend at the same speed as the descending speed of the lower plunger 114.

Meanwhile, as illustrated in FIGS. 7 and 9, the circulation flow path 130 according to the present invention may be installed at the outer circumference of the chamber 115 and connect the lower portion of the chamber 115 and the upper portion of the chamber 115.

Specifically, one end of the circulation flow path 130 connected to the upper portion of the chamber 115 is a discharge port 136 for discharging the working oil to the chamber 115, the other end of the circulation flow path 130 connected to the lower portion of the chamber 115 is the chamber It is an inlet 131 to which the hydraulic oil located at 115 is introduced.

And in the middle of the circulation passage 130, the chamber 115 and the opening and closing portion 120 are mounted in the vertical direction, the opening and closing portion 120 is mounted on the rotating shaft of the stepping motor 121 and the stepping motor 121 as described above. It comprises a thread shaft (123) to be converted to a rotational motion to a linear motion and a stem (123) mounted on the tip of the thread shaft 122 to reciprocate linearly, orifice type timing device (100) The housing 125 surrounding the stem 123 is inserted into the hole formed in the body 110.

Therefore, by the operation of the stepping motor 121, the stem 123 opens and closes the circulating flow path 130 when linearly moving inside the housing 125, extending from the inlet 131 formed in the lower portion of the chamber 115 The inlet pipe 132 extends to the middle of the length of the housing, and communicates with the inlet through hole 133 formed in the middle of the length of the housing 125.

In addition, the discharge pipe 135 extending from the discharge through hole 134 formed at the tip of the housing 125 extends to the discharge port 136 formed on the upper portion of the chamber 115.

In this way, the circulation flow path 130 is formed by connecting the inlet pipe 132, the housing 125, and the discharge pipe 135.

The circulation path 130 as the stem 123 that reciprocates linearly in the housing 125 opens and closes the housing 125 between the discharge through hole 134 and the inflow through hole 133 formed in the housing 125. Through it, the hydraulic oil is opened to flow or blocked from flowing.

More specifically, the distal end of the housing 125 in which the discharge through hole 134 is formed is an expanded structure, and an inner diameter is formed larger than the middle of the length of the housing 125 in which the inlet through hole 133 is formed. Therefore, the step 125S according to the difference between the inner diameter (large diameter) of the tip of the housing 125 and the middle inner diameter (small diameter) of the length of the housing 125 is formed at the tip of the housing 125.

In addition, a head 123H is formed at a front end of the stem 123 in a direction perpendicular to the length of the stem 123, and a side surface of the head 123H is in the middle of the length of the housing 125 where the inflow through hole 133 is formed. You come into contact with the inner circumference.

That is, when the head 123H of the stem 123 is located in the middle of the length of the housing 125, the side surface of the head 123H and the inner circumferential surface in the middle of the length of the housing 125 are brought into contact with the inflow through hole 133 The hydraulic oil does not flow into the discharge through hole 134 and is blocked.

When the stepping motor 121 operates in this blocked state and the stem 123 advances, the head 123H of the stem 123 advances toward the tip of the housing 125 and eventually the step 125S of the housing 125 As shown in FIG. 9, a gap (hereinafter referred to as “orifice G”) is formed between the head 123H and the step 125S, and the orifice after the hydraulic oil flows into the inflow through hole 133. After flowing to the front end of the housing through (G), it is circulated while being discharged into the chamber 115 through the discharge through hole 134 and the discharge port 136 formed on the upper portion of the chamber 115 through the discharge pipe.

Meanwhile, the circulation flow path 130 formed as described above may be a pipe or a pipe. When the circulation flow path 130 is opened by the operation of the opening/closing unit 120, the hydraulic oil may move from the lower portion of the chamber 115 to the upper portion of the chamber 115. When the circulation flow path 130 is closed, the hydraulic pressure located at the lower portion of the chamber 115 cannot move, so that the lower pressure of the chamber 115 may be increased.

The inlet pipe 132 is a pipe formed from the inlet 131 formed in the lower portion of the chamber 115 to a point corresponding to the inlet through hole 133 of the housing 125. When the upper plunger 113 is raised, the logic turn valve 140 may open the lower portion of the chamber 115 and the inlet pipe 132. Accordingly, the inlet pipe 132 may allow the hydraulic fluid located in the lower portion of the chamber 115 to be moved to the opening/closing unit 120. When the upper plunger 113 descends, the logic turn valve 140 may block the lower portion of the chamber 115 and the inlet pipe 132. Accordingly, the hydraulic oil located in the lower portion of the chamber 115 cannot be moved to the opening/closing part 120 through the inlet pipe 132.

The upper plunger 113 and the discharge pipe 144 formed in the guide 142 for guiding the vertical movement of the lower plunger 114 may be communicated with or blocked from the inlet pipe 132 as the lower plunger 114 moves up and down.

The discharge pipe 144 may be blocked from the inlet pipe 132 when the lower plunger 114 rises, thereby preventing the hydraulic fluid located at the bottom of the chamber 115 from moving to the inlet pipe 132.

When the lower plunger 114 descends, the discharge pipe 144 communicates with the inlet pipe 132 to move the hydraulic oil located in the lower portion of the chamber 115 to the inlet pipe 132. In this case, when the opening and closing portion 120 opens the inlet pipe 132 and the discharge pipe 135, the upper portion of the chamber 115 can receive a larger amount of hydraulic oil than when only the inlet pipe 132 is opened. have. Accordingly, the descending speed of the upper plunger 113 may be faster. The discharge pipe 144 may be a pipe having a smaller diameter than the inlet pipe 132 or a pipe such as a pipe. The discharge pipe 144 may be installed at a lower portion of the chamber 115 so as to be positioned below the inlet pipe 132.

The discharge pipe 135 is a pipe connecting the opening/closing portion 120 and the discharge port 136 formed on the upper portion of the chamber 115. When the upper plunger 113 rises, the opening/closing part 120 opens the circulation passage 130 so that the lower part of the chamber 115 communicates with the upper part of the chamber 115, and the working oil located at the lower part of the chamber 115 is introduced into the inlet pipe ( 132) and the discharge pipe 135 can be moved to the top of the chamber 115. The discharge pipe 135 may be installed on the outer circumference of the chamber 115 to be positioned above the opening/closing portion 120. The discharge pipe 135 may be a pipe or a pipe such as a pipe.

The non-return valve 140 may be installed inside the chamber 115. When the upper plunger 113 rises, the logic turn valve 140 may communicate the upper portion of the chamber 115 and the lower portion of the chamber 115. When the upper plunger 113 descends, the logic turn valve 140 may block the upper portion of the chamber 115 and the lower portion of the chamber 115. Logic turn valve 140 may be coupled to the outer peripheral surface of the guide mechanism. The logic turn valve 140 may include a support mechanism 141 and a receiving hole 143.

The support mechanism 141 may elastically support the head portion provided at the top of the upper plunger 113. A spring for supporting the support mechanism 141 with an elastic force may be installed inside the support mechanism 141. Spring one side is coupled to the guide mechanism, the other side can be coupled to the upper portion of the support mechanism (141). Accordingly, the support mechanism 141 may elastically support the head portion of the upper plunger 113. In the spring, when the upper plunger 113 rises, the support mechanism 141 may be moved upward by an elastic force. The support mechanism 141 may communicate the receiving hole 143 and the inlet pipe 132 as the upper plunger 113 rises. At this time, the hydraulic oil located in the receiving hole (143). That is, the hydraulic oil located in the lower portion of the chamber 115 may move to the inlet pipe 132. When the upper plunger 113 descends, the spring may be compressed by the load of the upper plunger 113. At this time, the support mechanism 141 may be moved in the downward direction, thereby blocking the receiving hole 143 and the inflow pipe 132.

The receiving hole 143 may be formed between the outer circumferential surface of the upper plunger 113 and the inner circumferential surface of the support mechanism 141. The receiving hole 143 may be filled with hydraulic oil. When the upper plunger 113 is raised, the head portion of the upper plunger 113 and the support mechanism 141 are separated, so that the working oil located at the upper portion of the chamber 115 passes through the receiving hole 143 to the lower portion of the chamber 115. Can be moved. In this case, when the circulation flow path 130 is closed by the opening/closing part 120, there is no place for the working oil to move, so that the pressure at the bottom of the chamber 115 is increased. In this state, when the lower plunger 114 is lowered, the head portion of the upper plunger 113 and the support mechanism 141 are contacted to block the movement of hydraulic oil and lower plunger 114 due to the lower pressure of the elevated chamber 115. ) And the upper plunger 113 may be filled with hydraulic oil. Accordingly, the orifice-type timing device 100 of the engine variable valve according to the present invention slows down the lowering speed of the upper plunger 113 compared to the lower plunger 114, thereby delaying the timing at which the intake valve closes the combustion chamber. Can be.

The opening/closing part 120 may be installed in the circulation passage 130. The opening/closing unit 120 is for opening and closing the circulation passage 130 connecting the inlet formed in the lower portion of the chamber 115 and the outlet formed in the upper portion of the chamber 115. Specifically, the opening/closing unit 120 may open between the inlet pipe 132 and the discharge pipe 135 so that the inlet pipe 132 and the discharge pipe 135 communicate. In this case, the hydraulic oil located in the lower portion of the chamber 115 may be moved to the upper portion of the chamber 115 through the inlet pipe 132 and the discharge pipe 135. The opening/closing unit 120 may close the inlet pipe 132 and the discharge pipe 135 so that the inlet pipe 132 and the discharge pipe 135 are blocked. The opening/closing unit 120 may be connected to the control unit 119 by at least one of wired communication and wireless communication.

The sensor unit 118 is for measuring the load of the engine. The sensor unit 118 may be installed to be connected to a governor, but is not limited thereto. If the engine load can be measured, it may be connected to another device or may be installed at another location. The sensor unit 118 may be connected to the control unit 119 by at least one of wired communication and wireless communication. Accordingly, the sensor unit 118 may provide the control unit 119 with a measurement load value that measures the engine load.

The control unit 119 is for controlling the opening/closing unit 120. The control unit 119 may control the opening/closing unit 120 to open and close the circulation flow path 130 according to the load of the engine measured by the sensor unit 118. For example, if the measurement load measured by the sensor unit 118 is equal to or greater than a preset reference load, the control unit 119 may operate the opening/closing unit 120 to open the circulation flow path 130. In this case, since the inlet pipe 132 and the discharge pipe 135 communicate, the hydraulic fluid located at the lower portion of the chamber 115 may be moved to the upper portion of the chamber 115. Accordingly, the upper plunger 113 may be lowered before the lower plunger 114 descends and opens the inlet pipe 132 and the outlet pipe 144. For example, the upper plunger 113 may descend together with the lower plunger 114 while being in contact with the lower plunger 114.

Therefore, the orifice-type timing device 100 of the variable valve for an engine according to the present invention accelerates the discharge time of the hydraulic oil when the engine load is high, thereby preventing the fall time of the upper plunger 113 from being delayed. ) Can be lowered almost simultaneously with the lower plunger 114. The reference load means that the amount of nitrogen oxide (NOx) is not large, the thermal efficiency and fuel efficiency are the optimal engine loads even if the timing of the intake valve closing the combustion chamber is not adjusted, and can be preset by the operator.

The control unit 119 may operate the opening/closing unit 120 so that the circulation flow path 130 is closed when the measurement load measured by the sensor unit 118 is less than a preset reference load. In this case, since the inlet pipe 132 and the discharge pipe 135 are blocked, the pressure under the chamber 115 may be increased. In this state, when the upper plunger 113 and the lower plunger 114 descend, the upper plunger 113 is separated from the lower plunger 114, and the working oil flows between the lower plunger 114 and the upper plunger 113. Can be supplied. Accordingly, the orifice-type timing device 100 of the variable valve for an engine according to the present invention delays the falling time of the upper plunger 113, and as a result, the time for the intake valve to close the combustion chamber can be delayed. Therefore, the orifice type timing device 100 of the variable valve for an engine according to the present invention increases the amount of air injected into the combustion chamber by increasing the amount of air injected into the combustion chamber by delaying the time when the intake valve closes the combustion chamber when the engine load is low. By increasing, it is possible to reduce the emission of nitrogen oxides (NOx), as well as improve fuel economy.

In addition, the stem 123 is moved back and forth by the operation of the stepping motor 121 of the opening/closing part 120 to open and close the circulation flow path 130, whereby the head 123H of the stem 123 of the housing 125 Located in the middle of the length, the orifice (G) formed between the side surface of the head (123H) and the inner surface of the housing (125) is closed, and the stem (123) advances to move the head (123H) out of the step, i.e., to the expanded area. By forming an orifice (G) between the head (123H) and the step (125S) to open the circulation path (130). Therefore, as the stem 123 is configured so that there is no site where an impact occurs due to interference with other components in the reciprocating motion of the forward and backward movement, the occurrence of the impact caused by the operation of the stepping motor 121 is basically eliminated, and thus the There is an advantage that reliability is increased and durability of the opening/closing unit 120 is increased.

In addition, the present invention can finely adjust the opening degree of the orifice (G) while moving the stem 123 back and forth using a stepping motor (121).

For example, when the thread shaft pitch of the thread shaft is 1.5 mm, when driving at 36 degrees with a stepping motor, the 0.15 mm orifice is opened and the timing delay effect is reduced compared to a completely closed state. That is, since the flow coefficient of the variable orifice is small, it takes a lot of resistance and delays the discharge time, so that a valve timing delay effect can be obtained. Thus, the opening degree of the variable orifice can be precisely controlled according to the precision of the rotation angle of the stepping motor. .

100: orifice type timing device
110: main body
113: upper plunger
114: lower plunger
115: chamber
120: opening and closing part
121: stepping motor
122: thread shaft
123: stem
123H: Head
125: housing
125S: Gap
130: circulation flow
131: inlet
132: inlet pipe
133: inflow through hole
134: discharge through hole
135: discharge pipe
136: outlet
140: logic turn valve

Claims (5)

It is mounted on the push rod 103 connecting the cam 101 and the rocker arm 105 that is rotated by the engine, and controls the flow of the working oil flowing along the circulation path formed therein to control the rocker arm 105 from the cam 101. ) As a timing device for a variable valve for an engine that controls the timing at which power is transmitted.
The upper plunger 113 and the lower plunger 114 moving up and down by the cam 101 are located, and a chamber 115 filled with hydraulic oil therein,
As the upper plunger 113 and the lower plunger 114 move upward, a circulation connecting the upper and lower portions of the chamber 115 so that hydraulic fluid located at the lower portion of the chamber 115 can flow toward the upper portion of the chamber 115 Euro 130,
It is mounted inside the circulation flow path 130 and moves along the circulation flow path 130 to close the circulation flow path 130 by coming into contact with the inner circumferential surface of the circulation flow path 130 or to orifice G between the inner circumferential surface of the circulation flow path 130. Stem 123 to form and open,
Motor 121 for generating power to move the stem 123,
The stem 123 located in the circulation passage 130 formed in the main body 110 of the orifice type timing device 100 is connected, and the main body 110 is configured to convert rotation of the motor 121 into linear reciprocating motion of the stem 123 The threaded shaft 122 fastened to,
Located inside the circulation passage 130 and includes a housing 125 that guides the linear reciprocating motion of the stem 123 in a state in which the stem 123 is accommodated therein,
An orifice-type timing device for a variable valve for an engine, characterized in that the circulation passage 130 extending from the lower part of the chamber 115 to the upper part of the chamber 115 penetrates the housing 125 and is formed inside the housing 125.
delete According to claim 1,
In the middle of the length of the housing 125, an inflow through hole 133 is formed so that the hydraulic oil introduced from the lower part of the chamber 115 flows into the housing 125, and at the tip of the housing 125, inside the housing 125 The discharge through hole 134 is formed so that the hydraulic oil is discharged to the upper portion of the chamber 115, and the tip of the housing 125 in which the discharge through hole 134 is formed is the length of the housing 125 in which the inlet through hole 133 is formed. An orifice-type timing device for a variable valve for an engine, characterized in that a step (125S) is formed between the discharge through hole (134) and the inlet through hole (133) with a more expanded structure than the middle.
According to claim 3,
The head 123H is formed on the stem 123, and the outer circumferential surface of the head 123H contacts the intermediate inner circumferential surface of the length of the housing 125 to block the flow of hydraulic oil, and the head 123H of the stem 123 is expanded Orifice-type timing device of the variable valve for an engine, characterized in that the orifice (G) is formed while moving to.
The method of claim 3 or 4,
The circulation passage 130 is,
The inlet 131 formed in the lower portion of the chamber 115, the inlet pipe 132 extending to the inlet through hole 133 of the housing 125, and the outlet 136 formed in the upper portion of the chamber 115, and the housing Orifice-type timing device for a variable valve for an engine, characterized in that it comprises a discharge pipe (135) extending from the discharge through hole (134) of the (125) to the discharge port (136).

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