KR101965243B1 - Regenerative suspension for vehicle - Google Patents

Abstract

An active suspension device for a vehicle is provided. The active suspension device for a vehicle comprises: an actuator formed of a piston arranged in a hydraulic cylinder to vertically reciprocate and divide the hydraulic cylinder into a tension chamber and a compression chamber; and a control system arranged at the outside of the actuator, enabling a fluid to circulate to flow into or be discharged from the hydraulic cylinder by movement of the piston, and generating a damping force or an action force required for the actuator.

Description

[0001] REGENERATIVE SUSPENSION FOR VEHICLE [0002]

The present invention relates to an active suspension system for a vehicle.

Generally, an active suspension system senses input information from a road surface through various sensors and controls it by an electronic control unit (ECU) to supply hydraulic pressure to an actuator, And the like.

Specifically, an actuator for compensating a displacement of a coil spring connected to a wheel of the vehicle is provided, and the amount of fluid supplied to the actuator is appropriately controlled to detect changes in roll and pitch of the vehicle to maintain a constant garage Thereby performing a function of improving the ride comfort and the road surface force of the vehicle

Furthermore, the level control of the garage enables the driver to set the height of the garage according to the condition of the road surface, or to reduce the air resistance by lowering the garage at high speed, thereby improving the stability of operation and fuel efficiency can do.

With respect to such an active suspension system, the flow rate of the fluid is controlled through a proportional control valve, but this proportional control valve is expensive, and the hydraulic pump used at this time is also expensive.

Furthermore, since the hydraulic pump is connected to the engine and is always driven, when the engine is in operation, the pump is always driven to generate a high-pressure source. Therefore, an excessive capacity not required by the system is required. There is a problem that the fuel consumption is adversely affected.

An embodiment of the present invention is to provide an active suspension system for a vehicle capable of attenuating the behavior of a vehicle such as a roll and a pitch through simple control and improving ride comfort.

According to an aspect of the present invention, there is provided an actuator comprising: a piston arranged in a hydraulic cylinder and reciprocating in an up-and-down direction and dividing the hydraulic cylinder into a tension chamber and a compression chamber; And a control system disposed outside the actuator and circulating the fluid to or from the hydraulic cylinder by movement of the piston and generating a damping force or an action force required for the actuator .

At this time, the control system includes a fluid line, one end of which is installed in the tension chamber, the other end of which is installed in the compression chamber and is closed in circulation; A valve unit installed in the fluid line for controlling the flow of the fluid; And an accumulator in which the fluid circulating through the fluid line is stored.

At this time, the valve unit may include first and second check valves, first and second blow-off valves, first and second on-off valves, and a flow control unit.

At this time, the first blow-off valve, the first check valve, the flow regulator, and the first on-off valve may be sequentially arranged in parallel on the fluid line between the tension chamber and the accumulator based on the actuator have.

At this time, the second blow-off valve, the second check valve, and the second on-off valve may be sequentially arranged in parallel on the fluid line between the compression chamber and the accumulator based on the actuator.

Wherein the control system comprises a bidirectional pump installed in the fluid line between the tension chamber and the accumulator; And a motor installed in the bidirectional pump for controlling the pump.

The valve portion may further include a third check valve disposed on the fluid line between the tension chamber and the accumulator, and the third check valve may prevent fluid flowing into the accumulator.

The active suspension system for a vehicle according to the present invention can easily control the attitude of the vehicle and improve the ride comfort by merely controlling the opening and closing of the valve unit and the bidirectional driving of the motor when the stroke of the actuator changes.

In addition, the active suspension system for a vehicle according to the present invention can easily control the posture of the vehicle through semi-active and active modes and improve ride comfort.

1 is a schematic view of an active suspension system for a vehicle according to an embodiment of the present invention.
2 is a schematic view showing a modified example of an active suspension system for a vehicle according to an embodiment of the present invention.
Fig. 3 is a schematic diagram showing a state in which the actuator shown in Fig. 1 performs a semi-active tensioning stroke. Fig.
FIG. 4 is a schematic view showing a state in which the actuator shown in FIG. 1 performs an active compression stroke. FIG.
Figure 5 is a schematic diagram illustrating the actuator shown in Figure 1 performing a semi-active compression stroke.
6 is a schematic view showing a state in which the actuator shown in FIG. 1 performs an active tensioning stroke.
7 is a schematic view showing a state in which the actuator shown in Fig. 2 performs a semi-active tensioning stroke. Fig.
8 is a schematic view showing a state in which the actuator shown in Fig. 2 performs an active compression stroke.
Figure 9 is a schematic diagram illustrating the actuator shown in Figure 2 performing a semi-active compression stroke.
10 is a schematic view showing a state in which the actuator shown in FIG. 2 performs an active tensioning stroke.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

In this specification, the terms "comprises" or "having" and the like refer to the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

1 is a schematic view of an active suspension system for a vehicle according to an embodiment of the present invention. 2 is a schematic view showing a modified example of an active suspension system for a vehicle according to an embodiment of the present invention.

In the following description, the tension chamber side is defined upward in the compression chamber and the compression chamber side in the tension chamber is defined upward in FIGS. 1 and 2.

As shown in FIG. 1, an active suspension system 1 for a vehicle according to an embodiment of the present invention may include an actuator 10, a control system 30, and the like.

In one embodiment of the present invention, the actuator 10 includes a hydraulic cylinder 12, a piston 14 and a piston rod 16. At this time, the actuator 10 receives the fluid from the control system 30 as shown in FIG. 1, and may be disposed on the left front wheel, the left rear wheel, the right front wheel, and the right rear wheel of the vehicle, respectively.

On the other hand, the hydraulic cylinder 12 can receive the fluid, and the piston 14 and the piston rod 16 can be disposed therein. The piston 14 may be connected to the piston rod 16 so as to reciprocate up and down inside the hydraulic cylinder 12. [ At this time, one side of the piston rod 16 may be coupled to the upper portion of the piston 14, and the other side thereof may be connected to the spring 3 or the vehicle body of the vehicle body.

The actuator 14 can be reciprocated upward or downward within the hydraulic cylinder 12 in accordance with the vibration or posture of the vehicle caused by an unspecified external force transmitted from the road surface to the vehicle.

At this time, the hydraulic cylinder 12 may include a compression chamber 12b, which is a lower side space of the piston 14 and a tension chamber 12a, which is an upper space of the piston 14 based on the piston 14. [ At this time, the volume of the tension chamber 12a and the compression chamber 12b may be changed by the reciprocating motion of the piston 14. [

1, the control system 30 is disposed outside the actuator 10 and supplies fluid to the actuator 10 to reciprocate the piston 14 thereby causing fluid to flow into the hydraulic cylinder 12 Or outflow. At this time, the control system 30 can generate a damping force or an active force required for the actuator 10. [

Meanwhile, in an embodiment of the present invention, the control system 30 may include a pump 32, a motor 34, a fluid line 36, a valve unit 40, and an accumulator. In one embodiment of the present invention, the pump 32 may be a bi-directional pump and may be configured to generate hydraulic pressure in the fluid used in the active suspension device 1 for a vehicle. In addition, the pump 32 serves to adjust the movement of the fluid in the active suspension system 1 of the vehicle, and more specifically, it is driven by using the motor 34. [

An active suspension device 1 for a vehicle according to an embodiment of the present invention is a structure in which a pump 32 is driven by a motor 34 and an electronic control unit controls the motor 34 The pump can be selectively driven, so that the effect of lowering the engine output and improving the fuel economy can be expected.

At this time, the pump 32 supplies the fluid to the actuator 10 on the front / rear wheel side of the left wheel of the vehicle at the same time by supplying the fluid to the actuator on the front / rear wheel side of the right wheel of the vehicle Can be supplied at the same time.

On the other hand, the accumulator 38 functions to receive and store the fluid when the flow rate of the fluid in the active suspension system 1 for a vehicle according to the embodiment of the present invention is excessive, It is possible to supply the fluid to each of the actuators 10 or the pump 32. In this case,

1, the fluid line 36 is a passage for movement of fluid between the control system 30 and the actuator 10, one end of which is installed in the tension chamber 12a and the other end is in the compression chamber 12b It is a closed loop fluid line connected to the installation.

Meanwhile, in one embodiment of the present invention, the valve unit 40 is disposed on the fluid line 36 to control the flow of the fluid. Referring to FIG. 1, the valve unit 40 includes first and second blow-off valves 42 and 43, a first and a second check valve 44 , 45, first and second on-off valves 48, 49, and a flow regulator 47.

On the other hand, the first blow-off valve 42, the first check valve 44, the flow rate regulator 47 and the first on-off valve 48 are connected to the tension chamber 12a and the accumulator 38). ≪ / RTI >

The second blow-off valve 43, the second check valve 45 and the second on-off valve 49 are connected to the fluid line 36 between the compression chamber 12b and the accumulator 38 on the basis of the actuator 10, In order.

On the other hand, the first and second blow-off valves 42, 43 are configured to limit the maximum pressure generated in the actuator 10 to prevent damage to the vehicle including the actuator 10, Can be maintained. The first and second check valves 44 and 45 and the first and second on-off valves 48 and 49 are configured to control the flow of the fluid flowing along the fluid line 36.

The first check valve 44 may then allow fluid to flow from the compression chamber 12b to the tension chamber 12a but conversely from flowing from the tension chamber 12a to the compression chamber 12b. The second check valve 45 may also allow fluid to flow from the accumulator 38 to the compression chamber 12b but conversely to prevent the fluid from flowing from the accumulator 38 to the compression chamber 12b.

In the embodiment of the present invention, the first and second check valves 44 and 45 are applied, but are not limited thereto and may be replaced with a pressure control valve or a flow control valve.

On the other hand, the flow regulator 47 may be a single valve assembly, a plurality of valve assemblies, or some other device or devices for regulating the flow of fluid flowing along the fluid line 36 . At this time, the flow control unit 47 can control the flow of the fluid flowing to the second check valve 45 and the second blow-off valve 43 when the fluid flows from the tension chamber 12a to the compression chamber 12b have.

On / off states of the first and second on-off valves 47 and 48 are determined depending on the active mode and the stroke change of the actuator 10. The first and second on-off valves 47 and 48 are opened and closed according to the active mode and the stroke change of the actuator 10, The opening and closing can be selectively controlled so that the fluid flows.

On the other hand, the control system 30 can be influenced by volume changes of the tension chamber 12a and the compression chamber 12b due to the reciprocating motion of the piston 14 during the tensioning or compression stroke of the actuator 10. [

Therefore, the fluid contained in the tension chamber 12a and the compression chamber 12b flows along the fluid line 36 to pass through the pump 32, and when the current is applied to the motor 34, The flow of fluid through the pump can be disturbed or facilitated, thereby creating the damping force or action force required of the actuator 10. [

Referring to FIG. 2, as an alternative to the control system 30 in one embodiment of the present invention, the valve portion 40a may further include a third check valve 146. As shown in FIG. On the other hand, the first blow-off valve 42, the first check valve 44, the flow rate regulating portion 47, the first on-off valve 48 and the third check valve 146 are arranged on the basis of the actuator 10 And may be arranged in parallel on the fluid line 36 between the tension chamber 12a and the accumulator 38 sequentially.

The third check valve 146 may allow fluid to flow from the pump 32 to the tension chamber 12a but vice versa from flowing from the tension chamber 12a to the pump 32. [ Also, in the embodiment of the present invention, the third check valve 146 is applied, but it is not limited thereto, and it may be replaced with a pressure control valve or a flow control valve.

The second blow-off valve 43, the second check valve 45 and the second on-off valve 49 are connected to the fluid line 36 between the compression chamber 12b and the accumulator 38 on the basis of the actuator 10, In order.

3 to 6, a method of controlling the active suspension device 1 of the vehicle according to the stroke of the actuator 10 will be described in detail.

Prior to the description, the arrows shown in Figs. 2 to 5 represent the flow of fluid, the x axis of the graph is the velocity of the piston 14, and the y axis is the y axis of the actuator 10 in order to be applied to the vehicle body (Force).

FIG. 3 is a schematic view showing a state in which the actuator 10 shown in FIG. 1 performs a semi-active mode and a tensile stroke. At this time, the active mode state may be a state where the vehicle is decelerating, accelerating, or cornering.

The active suspension device 1 according to an embodiment of the present invention is configured to open and close the first and second on-off valves 48 and 49 in accordance with the half-active mode, the active mode and the stroke change of the actuator 10, Can be selectively controlled.

Hereinafter, the rotation direction of the motor 34 is defined as a normal direction when the direction of the fluid flowing through the pump 32 is the same as the flow direction of the fluid, and is defined as a reverse direction when the direction is different from the flow direction of the fluid .

Referring to FIG. 3, when the actuator 10 performs a semi-active tensile stroke, when the piston 14 moves in the tensile direction, the semi-active rebound force is generated by lowering the pressure in the flow rate regulator 47 have. At this time, as the piston 14 pushes the fluid in the tension chamber 12a, the fluid can flow to the flow rate control section 47. [

At this time, the first on-off valve 48 and the second on-off valve 49 are controlled to be closed and the current of the motor 34 is applied when the fluid in the tension chamber 12a reaches the pump 32 To control the current applied to the motor so that fluid can flow from the accumulator 38 to the compression chamber 12b via the pump 32 when the damping force is needed.

4 is a schematic view showing a state in which the actuator 10 shown in Fig. 1 performs the active mode and the compression stroke.

Referring to FIG. 4, when the actuator 10 is in the active mode and the compression stroke, when the piston 14 moves in the compression direction, an active compression force may be generated. At this time, it means that the piston 14 can be actively pushed and compressed.

This allows the fluid to flow to the second on-off valve 49 as the piston 14 pushes the fluid in the compression chamber 12b. At the same time, current may be applied to the motor 34 connected to the pump 32 to allow fluid to flow from the accumulator 38 to the tension chamber 12a through the pump.

At this time, the first on-off valve 48 is closed, the second on-off valve 49 is controlled to be open, the fluid received in the compression chamber 12b flows to the accumulator 38, To the tension chamber 12a. Also, when the fluid flows from the pump 32 to the tension chamber 12a, the fluid can flow to the flow regulator 47, and a pressure drop of the fluid may be generated through the flow regulator.

5 is a schematic diagram showing a state in which the actuator 10 shown in FIG. 1 performs a semi-active mode and a compression stroke.

Referring to FIG. 5, when the actuator 10 performs the semi-active mode and the compression stroke, when the piston 14 moves in the compression direction, the anti-active compression force is generated . At this time, as the piston 14 pushes the fluid in the compression chamber 12b, the fluid can flow through the first check valve 44 to the pump 32 and the tension chamber 12a.

At this time, the first and second on-off valves 48 and 49 are controlled to be closed, and the fluid contained in the compression chamber 12b is supplied to the pump 32 and the tension chamber 12a via the first check valve 44, Lt; / RTI > When the fluid in the compression chamber 12b reaches the pump 32, the current of the motor 34 is applied to control the closed state, or when a small damping force is required, the current to be applied to the motor is controlled, To the accumulator 38, as shown in FIG.

6 is a schematic view showing a state in which the actuator 10 shown in FIG. 1 performs the active mode and the tensile stroke.

Referring to FIG. 6, when the actuator 10 is performing the active mode and the tension stroke, the active compression force can be generated when the piston 14 moves in the tension direction. At this time, it means that the piston 14 can be actively pushed and pulled.

This allows the fluid to flow to the first on-off valve 48 as the piston 14 pushes the fluid in the tension chamber 12a. At the same time, current may be applied to the motor 34 connected to the pump 32 to allow fluid to flow from the accumulator 38 to the tension chamber 12a through the pump.

At this time, the first on-off valve 48 is opened, the second on-off valve 49 is controlled to be closed, and the fluid contained in the tension chamber 12a and the accumulator 38 is supplied to the first on- To the compression chamber 12b. Also, when the fluid flows from the pump 32 to the tension chamber 12a, the fluid can flow to the flow regulator 47, and a pressure drop of the fluid may be generated through the flow regulator.

Hereinafter, a method of controlling the active suspension device 1a of the vehicle according to the stroke of the actuator 10 will be described in detail with reference to FIGS. 7 to 10. FIG.

7 is a schematic diagram showing a state of performing the semi-active mode and the tensile stroke of the actuator 10 shown in Fig. At this time, the active mode state may be a state where the vehicle is decelerating, accelerating, or cornering.

Referring to FIG. 7, when the actuator 10 performs a semi-active tensile stroke, when the piston 14 moves in the tensile direction, the semi-active rebound force can be generated by lowering the pressure in the flow rate regulator 47 have. At this time, as the piston 14 pushes the fluid in the tension chamber 12a, the fluid can flow to the flow rate control section 47. [

At this time, the first on-off valve 48 and the second on-off valve 49 are controlled to be closed and the third check valve 146 is closed before the fluid in the tension chamber 12a reaches the pump 32 To the pump (32).

8 is a schematic view showing a state in which the actuator 10 shown in Fig. 2 performs an active mode and a compression stroke.

Referring to FIG. 8, when the actuator 10 performs the active mode and the compression stroke, an active rebound force may be generated when the piston 14 moves in the compression direction. At this time, it means that the piston 14 can be actively pushed and compressed.

This allows the fluid to flow to the second on-off valve 49 as the piston 14 pushes the fluid in the compression chamber 12b. Simultaneously, a current is applied to the motor 34 connected to the pump 32 so that fluid can flow from the accumulator 38 through the pump to the tension chamber 12a via the third check valve 146.

At this time, the first on-off valve 48 is closed, the second on-off valve 49 is controlled to be open, the fluid received in the compression chamber 12b flows to the accumulator 38, To the tension chamber 12a. Also, when the fluid flows from the pump 32 to the tension chamber 12a, the fluid can flow to the flow regulator 47, and a pressure drop of the fluid may be generated through the flow regulator.

9 is a schematic diagram showing a state in which the actuator 10 shown in Fig. 2 performs a semi-active mode and a compression stroke.

Referring to FIG. 9, when the actuator 10 performs the semi-active mode and the compression stroke, when the piston 14 moves in the compression direction, the semi-active compression force is generated . At this time, as the piston 14 pushes the fluid in the compression chamber 12b, the fluid can flow through the first check valve 44 to the pump 32 and the tension chamber 12a.

At this time, the first and second on-off valves 48 and 49 are controlled to be closed and the fluid contained in the compression chamber 12b can be flowed to the tension chamber 12a via the first check valve 44 . It is also possible to prevent the third check valve from flowing to the pump 32 before the fluid in the compression chamber 12b reaches the pump 32.

10 is a schematic view showing a state in which the actuator 10 shown in Fig. 2 performs the active mode and the tensile stroke.

Referring to FIG. 10, when the actuator 10 is in the active mode and the tension stroke, when the piston 14 moves in the tension direction, an active rebound force may be generated. At this time, it means that the piston 14 can be actively pushed and pulled.

This allows the fluid to flow to the first on-off valve 48 as the piston 14 pushes the fluid in the tension chamber 12a. Simultaneously, current may be applied to the motor 34 connected to the pump 32 so that fluid can flow from the accumulator 38 through the third check valve 146 to the tension chamber 12a through the pump.

At this time, the first on-off valve 48 is opened, the second on-off valve 49 is controlled to be closed, and the fluid contained in the tension chamber 12a and the accumulator 38 is supplied to the first on- To the compression chamber 12b. Also, when the fluid flows from the pump 32 to the tension chamber 12a, the fluid can flow to the flow regulator 47, and a pressure drop of the fluid may be generated through the flow regulator.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the scope of the invention is not limited to the disclosed exemplary embodiments, 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 appended claims.

1, 1a: active suspension device for vehicle 3: spring
10: Actuator 12: Hydraulic cylinder
12a: tension chamber 12b: compression chamber
14: piston 16: piston rod
30: control system 32: pump
34: motor 36: fluid line
38: accumulator 40, 40a: valve part
42: first blow-off valve 43: second blow-off valve
44: first check valve 45: second check valve
47: Flow control unit 48: First on-off valve
49: second on-off valve 146: third check valve

Claims (7)

An actuator disposed in the interior of the hydraulic cylinder and configured to reciprocate up and down and to divide the hydraulic cylinder into a tension chamber and a compression chamber; And
And a control system disposed outside the actuator and circulating the fluid to or from the hydraulic cylinder by movement of the piston and generating a damping force or an action force required of the actuator,
The control system comprising: a fluid line having one end thereof installed in the tension chamber and the other end installed in the compression chamber and closed in circulation;
A valve unit installed in the fluid line for controlling the flow of the fluid; And
And an accumulator in which fluid circulating through the fluid line is stored,
The valve
First and second check valves, first and second blow-off valves, first and second on-off valves, and a flow regulator,
Wherein the first on-off valve is opened only during an active tension stroke, and the second on-off valve is opened only during an active compression stroke. delete delete The method according to claim 1,
Wherein the first blow-off valve, the first check valve, the flow regulator, and the first on-off valve are arranged in parallel on the fluid line between the tension chamber and the accumulator on the basis of the actuator, Device. The method according to claim 1,
Wherein the second blow-off valve, the second check valve, and the second on-off valve are sequentially arranged in parallel on the fluid line between the compression chamber and the accumulator based on the actuator. The method according to claim 1,
The control system
A bidirectional pump installed in the fluid line between the tension chamber and the accumulator; And
And a motor provided in the bidirectional pump for controlling the pump. The method according to claim 1,
Wherein the valve portion further comprises a third check valve disposed on the fluid line between the tension chamber and the accumulator, and wherein the third check valve blocks the fluid entering the accumulator.

Images