VEHICLE HEIGHT CONTROL SYSTEM

A vehicle height control system includes an arm including a first end portion connected to a vehicle body and a second end portion coupled to a wheel, a bearing unit fixed to the vehicle body, a crank coupled to the bearing unit, a push rod including a first end portion connected to the crank and a second end portion connected to the arm, and a spring reaction force variable device coupled to the bearing unit and configured to vary reaction force applied to the crank.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2023-0028900, filed on Mar. 6, 2023, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE PRESENT DISCLOSURE

Field of the Present Disclosure

The present disclosure relates to a vehicle height control system. More particularly, it relates to a vehicle height control system capable of controlling vehicle height and roll behavior of a vehicle by controlling input torque of a separate spring reaction force variable device depending on the load state of the vehicle.

Description of Related Art

Generally, a vehicle and a means of transportation use a suspension including a spring device having elastic force and a damper device having absorbing force, and the suspension serves as a device configured to maintain vehicle height, which is the vertical distance of the highest point of the vehicle from the ground plane, to support the weight of the vehicle, and to mitigate the impact the vehicle receives from the ground.

When a vehicle having a high center of gravity, such as a large bus or a double-decker bus, is traveling on the road, overturning of the vehicle may occur due to a rapid rolling motion caused by sudden steering. To reduce the risk of such an accident, it is required not only to change damping force of the suspension but also to adjust vehicle height by lowering a vehicle body.

On the other hand, when a vehicle having low vehicle height is traveling on the road, the lower side of a vehicle body or a bumper may contact with a speed bump or a protruding portion on the road surface. Therefore, a vehicle height adjustment device configured to adjust the vehicle height is provided in a vehicle having low vehicle height. The vehicle height adjustment device controls the vehicle height by driving a motor. However, generally, because power is continuously supplied to the motor to prevent back drive of the motor after vehicle height adjustment is performed by the vehicle height adjustment device, energy consumption of the vehicle may increase. Accordingly, it is necessary to solve a problem related to energy consumption.

Meanwhile, the vehicle height adjustment device, generally, adjusts, depending on the load state of a vehicle occupant or baggage, the vehicle height within the range of load conditions of curb weight and gross vehicle weight (GVW). That is, a change in adjustable payload is limited. Recently, as types of vehicles become more diverse, a purpose built vehicle (refer to hereinafter as PBV) has emerged on the market. In the case of a detachable transporter among PBVs, when a business box (a main body) is detached from the transporter in the forward-and-rearward direction, there is a significant difference between a payload to be supported when the transporter exists independently and a payload to be supported when the same has the business box attached thereto. Therefore, there is a need for a technique capable of controlling the vehicle height depending on a much wider range of vehicle load states.

Meanwhile, while a vehicle is traveling on the road, vibrations such as rolling, pitching, and yawing occur in addition to vertical bouncing of the vehicle body. In the instant case, a suspension system is used to reliably absorb these vibrations to improve ride comfort as well as steering stability. Among the vibrations, the movement of the vehicle body from side to side is referred to as rolling, and when the present rolling occurs, ride comfort and driving stability of the vehicle may deteriorate and deformation of the vehicle body may occur. For the present reason, the suspension system of the vehicle is provided with a device configured to prevent rolling of the vehicle body.

For example, the suspension system includes a stabilizer bar configured to prevent a vehicle from shaking from side to side and to maintain parallelism of a vehicle body. Here, the stabilizer bar controls roll behavior of a vehicle by torsion generated by a phase difference between a bump stroke and a rebound stroke of a left or right wheel of the vehicle. However, such a vehicle roll control device has a limitation in controlling roll behavior generated by active movement of a vehicle due to a characteristic of the stabilizer bar configured to control roll behavior of a vehicle. Accordingly, there is a problem in that it is impossible to provide both stability and ride comfort of a vehicle only using a stabilizer bar including a fixed rigidity.

BRIEF SUMMARY

Various aspects of the present disclosure are directed to providing a vehicle height control system configured for controlling vehicle height and roll behavior of a vehicle by controlling input torque of a separate spring reaction force variable device depending on the load state of the vehicle.

Furthermore, various aspects of the present disclosure are directed to providing a vehicle height control system configured for maintaining vehicle height in a state in which continuous driving force of a motor is not applied through a clutch unit located in a spring reaction force variable device.

The objects of the present disclosure are not limited to the above-mentioned objects, and other technical objects not mentioned herein will be clearly understood by those skilled in the art from the detailed description of the embodiments. Furthermore, the objects of the present disclosure may be achieved by means indicated in the scope of the claims and a combination thereof.

Various aspects of the present disclosure are directed to providing a vehicle height control system including an arm including a first end portion connected to a vehicle body and a second end portion coupled to a wheel, a bearing unit fixed to the vehicle body, a crank coupled to the bearing unit, a push rod including a first end portion connected to the crank and a second end portion connected to the arm, and a spring reaction force variable device coupled to the bearing unit and configured to vary reaction force applied to the crank.

In an exemplary embodiment of the present disclosure, the spring reaction force variable device may further include a motor configured to provide torque, a clutch unit connected to an output shaft of the motor, a reducer located at an output end portion of the clutch unit and coupled to the crank, and a spring portion coupled to the reducer. Reaction torque of the spring portion may be varied by driving the motor.

In another exemplary embodiment of the present disclosure, in the spring reaction force variable device, when the motor is driven, motor torque may be applied to the reducer coupled to the output end portion so that the motor torque on the reducer, the reaction torque of the spring portion, and load torque by an external load applied to the reducer through the crank are balance, and when the motor is not driven, the reaction torque and the load torque may be in balance.

In various exemplary embodiments of the present disclosure, the clutch unit may rotate only when the torque is input through the output shaft of the motor.

In various exemplary embodiments of the present disclosure, the reducer may be formed of a planetary gear set, and the planetary gear set may include a sun gear coupled to the output end portion of the clutch unit, a ring gear fixed to the spring portion, a plurality of planetary gears located and engaged between the sun gear and the ring gear, and a carrier including a first end portion connected to the planetary gears and a second end portion connected to the bearing unit.

In still various exemplary embodiments of the present disclosure, the spring portion may further include a frame fixed to the vehicle body, an elastic portion including one end portion fixed to the frame, and a ring gear fixing portion including the other end portion of the elastic portion fixed thereto, the ring gear fixing portion being coupled to the ring gear.

In a further exemplary embodiment of the present disclosure, the elastic portion may include a first elastic portion located adjacent to the frame and a second elastic portion located adjacent to the ring gear.

In another further exemplary embodiment of the present disclosure, the bearing unit may include a bearing case fixed to the vehicle body, a rod portion formed to be integrated with the crank and supported by the bearing case, a spring coupling portion located at one end portion of the rod portion and coupled to a torsion spring, and a variable device coupling portion located at the other end portion of the rod portion and coupled to the spring reaction force variable device.

In yet another further exemplary embodiment of the present disclosure, the bearing case may further include a support bearing configured to rotatably support the rod portion.

In yet another further exemplary embodiment of the present disclosure, the torsion spring and the spring coupling portion may be coupled to each other through a tooth-meshing structure or a bolt fastening structure.

In still yet another further exemplary embodiment of the present disclosure, an output end portion of the spring reaction force variable device and the variable device coupling portion may be coupled to each other through a tooth-meshing structure or a bolt fastening structure.

Various aspects of the present disclosure are directed to providing a vehicle height control system including an arm including a first end portion connected to a vehicle body and a second end portion coupled to a wheel, a bearing unit fixed to the vehicle body, a crank coupled to the bearing unit, a push rod including a first end portion connected to the crank and a second end portion connected to the arm, a spring reaction force variable device coupled to the bearing unit and configured to vary reaction force applied to the crank, and a control unit configured to perform, when a measured vehicle height exceeds a preset vehicle height range, driving of the spring reaction force variable device.

In an exemplary embodiment of the present disclosure, the spring reaction force variable device may further include a motor configured to provide torque, a clutch unit connected to an output shaft of the motor, a reducer located at an output end portion of the clutch unit and coupled to the crank, and a spring portion coupled to the reducer. Reaction torque of the spring portion may be varied by driving the motor.

In another exemplary embodiment of the present disclosure, the control unit may perform driving of the motor when the measured vehicle height exceeds the preset vehicle height range.

In various exemplary embodiments of the present disclosure, the control unit may be configured to determine an amount of change in the vehicle height according to each driving of the motor, and to set the number of times of the driving of the motor based on the determined amount of change in the vehicle height.

In various exemplary embodiments of the present disclosure, the reducer may be formed of a planetary gear set, and the planetary gear set may include a sun gear coupled to the output end portion of the clutch unit, a ring gear fixed to the spring portion, a plurality of planetary gears located to move between the sun gear and the ring gear, and a carrier including a first end portion connected to the planetary gears and a second end portion connected to the bearing unit.

In still various exemplary embodiments of the present disclosure, the control unit may convert a target control amount of the vehicle height into a target rotation amount of the carrier and may drive the motor so that the carrier is rotated up to a target location.

In a further exemplary embodiment of the present disclosure, the bearing unit may include a bearing case fixed to the vehicle body, a rod portion formed to be integrated with the crank and supported by the bearing case, a spring coupling portion located at one end portion of the rod portion and coupled to a torsion spring, and a variable device coupling portion located at the other end portion of the rod portion and coupled to the spring reaction force variable device.

Other aspects and exemplary embodiments of the present disclosure are discussed infra.

It is understood that the terms “vehicle”, “vehicular”, and other similar terms as used herein are inclusive of motor vehicles in general, such as passenger vehicles including sports utility vehicles (SUV), buses, trucks, various commercial vehicles, watercraft including a variety of boats and ships, aircraft, and the like, and include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from resources other than petroleum). As referred to herein, a hybrid vehicle is a vehicle that has two or more sources of power, for example, vehicles powered by both gasoline and electricity.

The above and other features of the present disclosure are discussed infra.

DETAILED DESCRIPTION

Hereinafter, reference will be made in detail to various embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings and described below. While the present disclosure will be described in conjunction with exemplary embodiments of the present disclosure, it will be understood that present description is not intended to limit the present disclosure to the exemplary embodiments of the present disclosure. On the other hand, the present disclosure is directed to cover not only the exemplary embodiments of the present disclosure, but also various alternatives, modifications, equivalents, and other embodiments, which may be included within the spirit and scope of the present disclosure as defined by the appended claims. The exemplary embodiments are provided to more completely describe the present disclosure to those skilled in the art.

Furthermore, terms such as “part” and “unit” described in the specification refer to a unit configured to process at least one function or operation, and the unit may be implemented by hardware or a combination of pieces of hardware.

Furthermore, in the present specification, when it is said that any part is positioned “on” or “above” another part, it means that the part is “directly on” the other part. In the instant case, another part may be positioned between the two parts. Furthermore, when it is said that any part is positioned “under” or “below” another part, it means that the part is “directly under” the other part. In the instant case as well, another part may be positioned between the two parts.

Furthermore, a control unit1600of the present specification may be implemented by an algorithm configured to control the operation of various components disposed in a vehicle, a memory configured to store data about a program that reproduces the algorithm, and a processor configured to perform the above-described operation using data stored in the memory. In the instant case, the memory and the processor may be implemented as separate chips. Alternatively, the memory and the processor may be implemented as a single chip. For example, the control unit1600may include at least one of an electronic control unit (ECU), a central processing unit (CPU), a microprocessor unit (MPU), a microcontroller unit (MCU), an application processor (AP), or any type of processor well known in the technical field of the present disclosure. Furthermore, the control unit1600may include at least one application configured to execute a method according to the exemplary embodiments of the present disclosure, or the same may be formed of a combination of software and hardware configured for performing an arithmetic operation on a program.

Furthermore, in each step, an identification code is used for convenience of description, and the identification code does not describe the order of each step. Each step may be performed in a different order from the order described in the exemplary embodiments unless a specific order is explicitly stated in the context.

Additionally, in the following embodiments, a reducer may be described with substantially the same configuration as a planetary gear set, and may be interpreted as including the planetary gear set as a type of reducer.

Furthermore, a wheel2000of a vehicle is described in the exemplary embodiment of the present disclosure, and each wheel2000of a multi-wheeled vehicle may move independently.

Furthermore, “height” included in the exemplary embodiment of the present disclosure may mean a distance between the center portion of the wheel2000and a vehicle body.

Various embodiments of the present disclosure relate to a vehicle height control system, and more particularly to a system configured for controlling the height of a vehicle body by controlling torque applied to a crank1200in response to torque of a motor1510located in a spring reaction force variable device1500.

FIG.1is a diagram illustrating a configuration of a vehicle height control system according to various exemplary embodiments of the present disclosure.

As illustrated in the drawing, the vehicle height control system includes an arm1000including one end portion fixed to a vehicle body and the other end portion coupled to the wheel2000. Here, the arm1000is coupled to the wheel2000through a knuckle, and the other end portion of the arm1000coupled to the wheel2000is configured to move in the vertical direction with respect to the one end portion coupled to the vehicle body.

Furthermore, the arm1000includes a bearing unit1100fixed to the vehicle body and the crank1200located in a direction perpendicular to the longitudinal direction of a rod portion1120formed in the bearing unit1100. The bearing unit1100includes a torsion spring1400and the spring reaction force variable device1500respectively coupled to the opposite end portions of the rod portion1120. A spring coupling portion1130and a variable device coupling portion1140are respectively disposed at the opposite end portions of the rod portion1120of the bearing unit1100, and the torsion spring1400and the spring reaction force variable device1500are respectively coupled to the spring coupling portion1130and the variable device coupling portion1140. The rod portion1120is located through a bearing case1110of the bearing unit1100. The crank1200is formed to be integrated with the rod portion1120and is located in the bearing case1110. Furthermore, the bearing case1110may further include a support bearing1121configured to be rotatable through the rod portion1120. The support bearing1121is fixed to the vehicle body so that the rod portion1120rotates freely.

The vehicle height control system includes a push rod1300located between the end portion of the crank1200and the end portion of the arm1000. The push rod1300is configured to move integrally with the end portion of the crank1200in response to the vertical movement of the arm1000. Furthermore, torque applied to the crank1200is transmitted to the rod portion1120according to the movement direction of the arm1000. The opposite end portions of the push rod1300are respectively coupled to the crank1200and the arm1000through a bearing, and the push rod1300is configured to move integrally with the arm1000in the vertical direction thereof. That is, when a change in vehicle height is applied, a torque is applied to the torsion spring1400and the spring reaction force variable device1500through the crank1200, and torque is applied to the crank1200in response to driving of the spring reaction force variable device1500, adjusting the vehicle height.

When the currently measured vehicle height via sensors exceeds a vehicle height range preset in the control unit1600, the control unit1600is configured to drive the motor1510to apply torque to the crank1200so that the vehicle height is adjusted, and to control a driving amount of the motor1510so that the vehicle height is adjusted within the preset vehicle height range.

The control unit1600may set a driving frequency of the motor1510so that the current vehicle height is controlled to be adjusted within the vehicle height range set in the control unit1600. That is, driving of the motor1510may be performed a plurality of times in response to a change in vehicle height which is variable in response to each driving of the motor1510.

A torque balance relationship of the spring reaction force variable device1500according to driving of the motor1510is included inFIG.4Cbelow, and a torque balance relationship of the spring reaction force variable device1500after driving of the motor1510stops is included inFIG.4D. According to the torque balance relationships included inFIGS.4C and4D, each torque balance relationship is newly set depending on the driving frequency of the motor1510.

The spring reaction force variable device1500coupled to the other side of the bearing unit1100is configured to rotate a carrier1525of the spring reaction force variable device1500by driving force of the motor1510. The driving force of the motor1510is converted into reaction torque of the carrier1525of the spring reaction force variable device1500, and the reaction torque is transmitted to the crank1200directly coupled to the rod portion1120of the bearing unit1100. The variable device coupling end portion of the bearing unit1100and the carrier1525may be bolted together, or the variable device coupling end portion and the carrier1525may be coupled to each other by a tooth-meshing structure.

The spring reaction force variable device1500is coupled to the rod portion1120of the bearing unit1100, and the torsion spring1400may apply torque to the rod portion1120according to driving of the motor1510. Furthermore, the spring reaction force variable device1500is configured to provide torque to an end portion of the crank1200formed to be integrated with the rod portion1120, the end portion being coupled to the push rod1300. Furthermore, when torque is applied to the spring reaction force variable device1500through the rod portion1120, the spring reaction force variable device1500is configured to rotate the carrier1525to achieve torque balance between the applied torque, reaction force of the spring reaction force variable device1500, and reaction torque of the torsion spring1400. Accordingly, the crank1200may be rotated integrally with the push rod1300in the height direction of the vehicle in response to the driving amount and driving frequency of the motor1510of the spring reaction force variable device1500.

FIG.2is an enlarged view of the bearing unit1100according to the exemplary embodiment of the present disclosure. As illustrated in the drawing, the bearing unit1100includes the bearing case1110coupled to a vehicle body, and the bearing case1110is located so that the rod portion1120is provided to penetrate the bearing case1110in the longitudinal direction of the vehicle. Furthermore, the bearing case1110through which the rod portion1120passes may include a support bearing configured to support the rod portion1120.

Furthermore, the vehicle height control system includes the crank1200fixed to the rod portion1120and located in the width direction of the vehicle. Accordingly, the other far end portion of the crank1200may be moved in the height direction of the vehicle in response to the rotation amount of the rod portion1120. The crank1200is coupled to the central area between the support bearings located on the rod portion1120, and the other end portion of the crank1200is moved integrally with the rod portion1120in the height direction in response to the rotation amount of the rod portion1120. The arm1000and the wheel2000are moved integrally in response to the movement of the crank1200in the height direction thereof.

The opposite end portions of the rod portion1120are respectively coupled to the torsion spring1400and the carrier1525of the spring reaction force varying device1500. The torsion spring1400may be located in parallel to the rod portion1120in the same direction, and the torsion spring1400may be fixed to the rod portion1120through the spring coupling portion1130located at one end portion of the rod portion1120.

The other end portion of the rod portion1120includes the variable device coupling portion1140configured to allow the carrier1525of the spring reaction force variable device1500to be coupled to the other end portion of the rod portion1120. That is, the driving torque of the motor1510, the reaction torque of the torsion spring1400, and the reaction torque applied from the spring reaction force variable device1500are transmitted to the crank1200through the rod portion1120. Furthermore, the torque applied through the crank1200and the reaction torque of the torsion spring1400are applied to the spring reaction force variable device1500through the rod portion1120.

The torsion spring1400and the carrier1525respectively coupled to the opposite end portions of the rod portion1120may be fixed to the rod portion1120through bolt fastening. Alternatively, a meshing gear may be provided at each of the opposite end portions of the spring coupling portion1130and the variable device coupling portion1140, and each of the torsion spring1400and the carrier1525may include a structure corresponding to the meshing gear formed in each of the spring coupling portion1130and the variable device coupling portion1140to be meshed with each other.

That is, the rod portion1120is coupled to the torsion spring1400and the spring reaction force variable device1500so that torque applied from each of the torsion spring1400and the spring reaction force variable device1500is transmitted to the crank1200.

FIG.3is a diagram illustrating the configuration of the spring reaction force variable device1500according to the exemplary embodiment of the present disclosure.

The spring reaction force variable device1500is fixed to the vehicle body, and the carrier1525of the spring reaction force variable device1500is coupled to one end portion of the rod portion1120of the bearing unit1100. Furthermore, the spring reaction force variable device1500includes the motor1510configured to apply torque, a clutch unit10coupled to an output shaft of the motor1510, and a reducer1520coupled to the output end portion300of the clutch unit10.

The reducer1520is rotated in response to torque applied from the output end portion300of the clutch unit10coupled to the reducer1520. Furthermore, a spring portion1530is provided between the vehicle body and the outside of the reducer1520. That is, the spring portion1530has one end portion coupled to a ring gear1523located at the edge portion of the reducer1520and the other end portion fixed to the vehicle body. Furthermore, the spring portion1530is configured to apply reaction torque applied between the vehicle body and the ring gear1523to the carrier1525of the reducer1520.

That is, torque applied from the motor1510is transmitted to the reducer1520through the clutch unit10, and the reducer1520is configured to determine the location of the carrier1525of the reducer1520based on resultant force of elastic force applied from the spring portion1530. Therefore, a positional relationship between components forming the reducer1520is set to achieve torque balance between the reducer1520, the carrier1525, the motor1510, and the rod portion1120coupled to the carrier1525.

According to the exemplary embodiment of the present disclosure, the reducer1520is formed of a planetary gear set, and the same includes a sun gear1521coupled to the output end portion300of the clutch unit10and located at the center portion thereof, and a ring gear1523configured to surround the outermost portion of the planetary gear set. Furthermore, a plurality of planetary gears1522located between the ring gear1523and the sun gear1521are provided. The external surface of the planetary gear set includes the carrier1525, coupled to the planetary gear1522and rotated integrally with the planetary gear1522, and the carrier1525is coupled to the rod portion1120of the bearing unit1100. The carrier1525is inserted into the center portion of the planetary gear1522and is rotated integrally with the planetary gear1522, and the carrier1525may be located substantially on the same axis as the output end portion300of the clutch unit10.

That is, while torque is applied to the sun gear1521from the output end portion300of the clutch unit10and the planetary gear1522is rotated in the opposite direction to the sun gear1521in response to rotation of the sun gear1521, the carrier1525is rotated in the same direction as the sun gear1521between the ring gear1523and the sun gear1521. Furthermore, when the planetary gear1522is rotated integrally with the carrier1525as described above, the ring gear1523is configured to rotate at a predetermined angle with respect to the vehicle body, and an elastic portion1531of the spring portion1530is configured to provide reaction torque to the ring gear1523rotating with respect to a frame1540.

The spring portion1530includes the frame1540fixed to the vehicle body, and the same is coupled to a ring gear fixing portion1524located on the ring gear1523of the reducer1520. When the ring gear1523is rotated, the elastic portion1531located between the frame1540and the ring gear fixing portion1524is configured to provide reaction torque between the frame1540and the ring gear1523in response to the rotation amount of the ring gear1523. Accordingly, the reaction torque applied through the spring portion1530in response to the rotation amount of the ring gear1523may be relatively increased.

When the motor1510is rotated to drive the sun gear1521, the elastic portion1531is configured to apply reaction torque to the ring gear1523in response to the rotation amount of the ring gear1523. Conversely, when the motor1510is not rotated, the elastic portion1531may provide reaction torque in response to the rotation amount between the ring gear1523and the frame1540by external torque applied to the carrier1525. That is, the elastic portion1531provides reaction torque in the opposite direction to the external torque introduced into the carrier1525to achieve torque balance of external torque introduced into the spring reaction force variable device1500.

The elastic portion1531may include one or more elastic portions1531having different spring constants corresponding to the deformation amount and reaction torque, and as various exemplary embodiments of the present disclosure, the elastic portion1531may include a torsional spring, a coil spring, and the torsion spring1400. Moreover, the elastic portion1531may be formed of a combination of one or more different spring types.

FIG.4Aillustrates, as various exemplary embodiments of the present disclosure, a configuration in which a first elastic portion1532and a second elastic portion1533forming the elastic portion1531are coupled to each other in series to apply reaction torque to the ring gear1523.

As illustrated in the drawing, the frame1540is fixedly located so as not to be rotated, and includes the first elastic portion1532located adjacent to the frame1540. The first elastic portion1532is coupled to the frame1540through a spring connection portion1534located in the frame1540. In the exemplary embodiment of the present disclosure, the spring connection portion1534may be coupled to the edge portion of the first elastic portion1532.

Furthermore, the second elastic portion1533located adjacent to the ring gear1523is provided. The second elastic portion1533is coupled to the ring gear fixing portion1524through the spring connection portion1534. The spring connection portion1534may be located adjacent to the edge portion of the second elastic portion1533coupled to the ring gear1523.

Furthermore, the first elastic portion1532and the second elastic portion1533may include the spring connection portion1534to be coupled to each other at a location adjacent to the central area. That is, the first elastic portion1532and the second elastic portion1533are connected in series.

Therefore, when the motor1510is driven, the ring gear1523is rotated by rotation force applied to the sun gear1521coupled to the output end portion300of the clutch unit10, and the frame1540and the ring gear fixing portion1524are switched to a relatively twisted state, and reaction torque of the elastic portion1531is generated.

Furthermore, when the motor1510is not driven, the output end portion300of the clutch unit10is fixed to limit the rotation of the sun gear1521, and reaction torque of the elastic portion1531coupled to the ring gear fixing portion1524and external torque of a load applied to the carrier1525are applied to the reducer1520. In the instant case, the elastic portion1531provides reaction torque in a direction opposite to the twisting direction. Accordingly, the carrier1525is rotated by an angle relatively smaller than the amount of torque applied from the outside thereof to achieve torque balance.

FIG.4Billustrates, as another exemplary embodiment of the present disclosure, a configuration in which the first elastic portion1532and the second elastic portion1533forming the elastic portion1531are coupled in parallel to each other to apply reaction torque to the ring gear1523.

As illustrated in the drawing, the elastic portion1531includes the first elastic portion1532located adjacent to the frame1540and the second elastic portion1533located adjacent to the side surface of the ring gear1523. The first elastic portion1532and the second elastic portion1533are coupled to each other by the spring connection portion1534formed to extend from the side of the ring gear1523. The spring connection portion1534located on the side of the ring gear1523is coupled to the edge portion areas of the first elastic portion1532and the second elastic portion1533.

Furthermore, the spring connecting portion1534formed to extend from the frame1540may be fixedly located at the central areas of the first elastic portion1532and the second elastic portion1533.

In another exemplary embodiment of the present disclosure, the elastic portion1531is configured to apply reaction torque between the ring gear1523and the frame1540when the motor1510is driven and the motor1510is not driven, making it possible to achieve, according to the driving relationship, torque balance between torque applied to the carrier1525, torque generated by driving the sun gear1521, and reaction torque applied to the ring gear1523through the elastic portion1531.

FIG.4Cis a diagram illustrating a mechanism configured to achieve torque balance in response to a driving input of the motor1510.

The control unit1600is configured to apply power to the motor1510, and when the output shaft of the motor1510is rotated, the clutch unit10coupled to the output shaft of the motor1510is rotated integrally with the motor1510. The reducer1520coupled to the output end portion300of the clutch unit10is configured to rotate the carrier1525by driving force of the output end portion300of the clutch unit10.

The sun gear1521coupled to the output end portion300of the clutch unit10is rotated in the same direction as the output end portion300of the clutch unit10, and each of the planetary gears1522located to be engaged with the sun gear1521is rotated in the opposite direction to the sun gear1521. Furthermore, each of the planetary gears1522moves between the sun gear1521and the ring gear1523, and the central axis of the planetary gear1522is configured to move in the same direction as the rotation direction of the sun gear1521. Furthermore, the carrier1525, formed to protrude from the external surface to be connected to the planetary gear1522and coupled to a load, is rotated in the same direction as the movement direction of the central axis of the planetary gear1522and the rotation direction of the sun gear1521.

Additionally, when the ring gear1523is rotated relative to the frame1540in response to the movement of the planetary gear1522, torsional force is applied to the spring portion1530located between the frame1540and the ring gear1523. Accordingly, the elastic portion1531of the spring portion1530is configured to apply reaction torque to the ring gear1523in response to relative torsion between the frame1540and the ring gear fixing portion1524.

Here,FIG.4Cillustrates a balance relationship after torque balance is achieved between the outputs of the carrier1525coupled to the outside in response to the input of the motor1510, the reducer1520, and the motor1510.

As illustrated in the drawing, torque of the sun gear1521acts counterclockwise when the motor1510is driven, and reaction torque of the spring portion1530coupled to the ring gear1523acts in the same direction as the torque of the sun gear1521. Conversely, reaction torque or torque applied from the carrier1525acts clockwise. Therefore, in torque balance, the sum of the torque of the motor1510and the reaction torque of the spring portion1530is in balance with the torque of the sun gear1521.

That is, when force applied from the motor1510to the sun gear1521is determined as Ts and reaction torque of the spring portion1530is applied in a state in which the ring gear1523in torque balance is fixed, torque Tc applied to the carrier1525is determined by multiplying 1+R (where R is the radius of the ring gear/the radius of the sun gear) by the force Ts applied to the sun gear1521. Furthermore, reaction torque Tr of the ring gear1523has R*Ts.

As described above, as illustrated in the drawing, when torque balance is achieved in response to the input of the motor1510, Tc=Tr+Ts is obtained, and when reaction torque is applied in a state in which the ring gear1523is fixed, a torque balance state including a value of Tc=(1+R)*Ts is achieved.

As various exemplary embodiments of the present disclosure,FIG.4Dillustrates movement to achieve an balance state, when driving force of the motor1510is released, between the reaction torque Tc of the carrier1525through the spring reaction force variable device1500and the reaction torque Tr applied from the outside of the spring reaction force variable device1500in a state in which rotation of the output end portion300of the clutch unit10is limited.

Here, the driving force of the motor1510is released, and torque applied to the sun gear1521is 0, which means a torque balance state between the reaction torque of the spring portion1530and the torque applied to the carrier1525.

As illustrated in the drawing, in the state in which the driving of the motor1510of the spring reaction force variable device1500is released, the output end portion300coupled to the sun gear1521is switched to a state in which driving torque is not applied from the motor1510. Accordingly, torque Tc of the carrier1525applied counterclockwise in the drawing is generated, and reaction torque Tr applied through the spring portion1530of the spring reaction force variable device1500is applied. Here, reaction torque applied from the outside of the spring reaction force variable device1500may include all external factors affecting the spring reaction force variable device1500through the carrier1525.

That is, when the input torque of the motor1510is converted to 0 after torque Ts of the motor1510is applied, the sun gear1521is fixed by the clutch unit10, and the carrier1525connected to the planetary gear1522is rotated to obtain an equilibrium state between Tc and Tr. For example, in the relationship of Tc>Tr, a relationship is established in which the carrier1525is rotated counterclockwise in the drawing and restored by the reaction torque Tc, and Tr applied by the spring portion1530increases. Here, in the torque balance relationship of the total planetary gears1522, new torque Tc_new of the carrier1525and new torque Tr_new of the spring portion1530are determined and represented as Tc_new=Tr_new in the balanced state.

That is, Ts torque to be applied when the motor1510is driven inFIG.4Cbecomes 0, and the Ts torque is configured to achieve a new balanced state through torque applied to the spring portion1530and torque output through the carrier1525. Accordingly, torque Ts/2 is applied to each of the spring portion1530and the carrier1525. In response to the torque Ts/2 applied thereto, a positional relationship of the ring gear1523coupled to the carrier1525and the spring portion1530is adjusted.

Wherein the Tc=θc×K1 and Tr=θr×K2

Additionally, according to a relationship between elastic modulus K2 of the spring portion1530and elastic modulus K1 applied to the carrier1525, the carrier1525and the planetary gear1522are moved to a new balanced position to be rotated clockwise in the drawing.

That is, the control unit1600may be configured to determine the rotation amount (angle) of the carrier1525and the planetary gear1522that achieve a new torque balance after driving of the motor1510is stopped, and to set the driving frequency of the motor1510based on the determined rotation amount. Furthermore, the control unit1600may set the driving frequency of the motor1510based on the rotation amount of the carrier1525rotated in response to each driving of the motor1510, making it possible to determine the rotation amount of the carrier1525.

According to the exemplary embodiment of the present disclosure, the control unit1600applies driving force of the motor1510as illustrated inFIG.4C, is configured to determine the rotation amount of the carrier1525by performing the step inFIG.4Dto obtain new torque balance based on the applied driving force, and repeatedly performs, based on the determined rotation amount, the steps inFIGS.4C and4Dto correspond to the predetermined rotation amount of the carrier1525.

FIG.5Ais a diagram illustrating a configuration relationship of the clutch unit10according to the exemplary embodiment of the present disclosure.

As illustrated in the drawing, the clutch unit10includes a housing100and a cover portion110disposed at one end portion of the housing100and configured to cover the open end portion of the housing100. The housing100includes a circular cross section, and the cover portion110is configured to completely cover the opening of one end portion of the housing100.

The clutch unit10further includes an output end portion300configured to penetrate the other end portion of the housing100and formed to have at least one flat surface. The housing100includes a plurality of lockers400disposed therein and configured to surround the flat surface of the output end portion300and a motor output shaft200disposed therein, the motor output haft200including one end portion inserted into an opening410located in each locker400. The output end portion300includes the number of flat surfaces corresponding to the number of lockers400located inside the housing100. The output end portion300in an exemplary embodiment of the present disclosure may have four flat surfaces corresponding to the four lockers400. Furthermore, the plurality of flat surfaces located at the output end portion300are respectively in contact with the plurality of adjacent lockers400when torque of the motor output shaft200is applied. Accordingly, the surfaces of the lockers400and the flat surfaces of the output end portion300may selectively contact with each other.

The motor output shaft200includes a rotation transmission portion210disposed at one end portion thereof and partially inserted into the opening410located in each locker400in the longitudinal direction and a driving transmission portion220disposed at the other end portion thereof and formed to penetrate the cover portion110to protrude outwards from the cover portion110. The driving transmission portion220is coupled to a driving portion configured to apply torque to be rotated integrally with the rotation direction of the driving portion.

Furthermore, torque of the driving portion is applied to the driving transmission portion220located at the other end portion of the motor output shaft200, and driving force applied to the driving transmission portion220is configured to rotate the output end portion300through the rotation transmission portion210. The driving portion is configured to transmit driving force capable of rotating the motor output shaft200, and the surfaces of the plurality of lockers400are respectively in contact with the flat surfaces of the output end portion300in response to the torque of the motor output shaft200. According to the exemplary embodiment of the present disclosure, the driving portion coupled to the motor output shaft200may be formed of the motor1510.

The motor output shaft200includes the rotation transmission portion210inserted into the opening410formed in each of the lockers400. Here, the motor output shaft200includes four rotation transmission portions210corresponding to the four lockers400in the exemplary embodiment of the present disclosure. Each of the rotation transmission portions210may maintain a state of being inserted into each of the openings410formed in the plurality of lockers400. Additionally, the rotation transmission portion210is rotated in the same direction as the rotation direction of the driving transmission portion220, and the locker400in contact with the rotation transmission portion210through the opening410is rotated integrally with the rotation transmission portion210in response to the rotation direction of the motor output shaft200.

A braking unit600located inside the housing100of the clutch unit10is configured to regulate movement of the plurality of lockers400when torque of the output end portion300is applied to the inside of the clutch unit10, and the torque of the output end portion300is not transmitted to the motor output shaft200. The braking unit600in an exemplary embodiment of the present disclosure includes a magnetic portion440located on the outermost side of the locker400, a steel portion500located on the internal circumferential surface of the housing100and disposed at a location corresponding to the magnetic portion440, and a braking portion510disposed adjacent to the steel portion500and configured to selectively contact with the locker400.

The plurality of lockers400are located inside the housing100, and each flat surface of the output end portion300and each locker400may be located adjacent to each other. The plurality of lockers400are divided into at least two pieces, and each locker400is disposed to include a predetermined gap between the flat surface of the output end portion300and the housing100. The number of flat surfaces of the output end portion300may be the same as the number of lockers400so that the internal surface of each locker400is located adjacent to the flat surface of the output end portion300.

Furthermore, when the torque of the motor output shaft200is applied, the internal end portion of the locker400may contact with the flat surface formed on the output end portion300, and the locker400may be spaced from the internal circumferential surface of the housing100with a predetermined distance so that the motor output shaft200, the locker400, and the output end portion300are integrally rotated without interference with the internal circumferential surface of the housing100.

The housing100includes the steel portion500disposed on the internal circumferential surface thereof, and at least one locker400includes the magnetic portion440disposed on the external circumferential surface thereof. Accordingly, when the torque of the motor output shaft200is released, the magnetic portion440of the locker400may be moved to a location close to the internal circumferential surface of the housing100. Furthermore, the braking unit600includes the braking portion510disposed adjacent to the steel portion500and located close to the internal circumferential surface of the housing100. Accordingly, the external circumferential surface of the locker400is moved to a location in contact with the braking portion510by magnetic force to limit the movement of the motor output shaft200.

Furthermore, when the torque of the output end portion300is applied, the flat surfaces formed on the output end portion300push the plurality of lockers400in the radial direction so that the braking portion510located on the internal circumferential surface of the housing100and the external circumferential surfaces of the lockers400contact with each other to be fixed to each other. Therefore, it is possible to prevent the torque of the output end portion300from being transmitted to the motor output shaft200. The braking portion510may be formed at a location closer to the locker400than to the steel portion500, making it possible to prevent the magnetic portion440of the locker400from directly contacting with the steel portion500.

The locker400and the internal circumferential surface of the housing100may be configured to form a predetermined gap therebetween according to the location of the locker400. Therefore, in a state in which driving force of the motor output shaft200is released, the external circumferential surface of the locker400is moved to a location adjacent to the internal circumferential surface of the housing100by magnetic force of the magnetic portion440, and a distance between the internal circumferential surface of the housing100and the external circumferential surface of the locker400becomes minimized.

Conversely, when the motor output shaft200is rotated, the rotation transmission portion210of the motor output shaft200may be located to contact one end portion in the width direction of the opening410of the locker400, and torque may be applied to rotate each locker400in the torque direction of the driving portion. In the instant case, the plurality of lockers400are located to respectively contact with the flat surfaces of the output end portion300, and the distance between the internal circumferential surface of the housing100and the external circumferential surface of the locker400is switched to the maximum state. Accordingly, the locker400is located in response to the rotation of the motor output shaft200to tightly contact with the surface of the output end portion300(that is, the surface of the output end portion300is constrained) without generating reaction force with the housing100.

As described above, the clutch unit10in an exemplary embodiment of the present disclosure is configured so that, in response to the motor output shaft200configured to rotate in a direction consistent with the rotation direction applied from the driving portion, the locker400is spaced from the internal circumferential surface of the housing100and is rotated integrally with the output end portion300. Furthermore, when the torque applied to the motor output shaft200is released, the braking portion510and the locker400contact with each other to limit the movement of the motor output shaft200, preventing back drive of the motor.

FIG.5Bis a diagram illustrating a configuration of the steel portion500located on the internal circumferential surface of the housing100and the braking portion510located adjacent to the steel portion500.

The steel portion500is located on the internal circumferential surface of the housing100to correspond to the magnetic portions440respectively located on the external circumferential surfaces of the plurality of lockers400. Therefore, when the torque of the motor output shaft200is released, the locker400is moved to a location adjacent to the steel portion500of the housing100by magnetic force. At the same time, the external surface of the locker400may contact with the braking portion510to limit the movement of the locker400and the motor output shaft200.

Furthermore, the braking portion510located adjacent to the steel portion500may be located closer to the center portion of the housing100than the steel portion500. Accordingly, when the locker400is moved to a location adjacent to the steel portion500in response to magnetic force, the external surface of the locker400is configured to contact with the braking portion510.

As illustrated in the drawing, the exemplary embodiment of the present disclosure may include the braking portion510having a predetermined step with the steel portion500, and the braking portion510may be located at at least a portion of the opposite end portions of the housing100in the longitudinal direction with respect to the steel portion500. The exemplary embodiment of the present disclosure may include the braking portion510located on at least a portion of the steel portion500in the longitudinal direction and configured to surround the internal circumferential surface of the housing100.

Therefore, when the locker400is moved to a location closest to the internal circumferential surface of the housing100, the magnetic portion440and the steel portion500are configured to maintain a non-contact state and to provide reaction force in a state in which the braking portion510and the locker400contact with each other.

FIGS.5C to5Eare diagrams illustrating a configuration in which torque of the motor output shaft200is applied and the motor output shaft200is rotated integrally with the locker400and the output end portion300.

As illustrated inFIG.5C, the motor1510is configured as a driving portion and is coupled to the driving transmission portion220of the motor output shaft200, and when torque of the motor1510is applied to the motor output shaft200, the rotation transmission portions210of the motor output shaft200respectively located at the openings410of the locker400are configured to initially press the openings410in the rotation direction of the motor output shaft200.

The pressurized openings410respectively move the plurality of lockers400so that the external surfaces of the lockers400are spaced from the braking portion510of the housing100, and accordingly, the plurality of lockers400are spaced from the internal circumferential surface of the housing100and switched to the rotatable state.

The opening410includes a trapezoidal shape, the long side surface of which is formed close to the external circumferential surface of the housing100. Furthermore, the inclined side surface of the trapezoidal shape is pressed by rotation force of the rotation transmission portion210. Force is applied to the locker400in a tangential direction in which the inclined side surface and the rotation transmission portion210contact with each other. The force applied to the inclined side surface is formed of a resultant force including a vertical force by which the locker400constrains the flat surface of the output end portion300and a horizontal force by which the locker400is rotated.

Furthermore, as illustrated in the drawing, in the exemplary embodiment of the present disclosure including four lockers400, the rotation transmission portions210respectively inserted into the openings410are rotated in the same direction, and each of the rotation transmission portions210contacts with a corresponding one of the end portions of the openings410to apply rotation force to the lockers400in the same direction.

Furthermore, the locker400includes a pressure protrusion420located at one end portion of the locker400, the pressure protrusion420being located at one end portion of the side surface of the locker400, the one end portion being close to the internal circumferential surface of the housing100. Furthermore, the locker400including the pressing protrusion420includes an insertion groove430configured to allow the pressure protrusion420to be inserted into the adjacent locker400. The pressure protrusion420is located to cross the insertion groove430in the longitudinal direction, and in the lockers400adjacent to each other, the insertion groove430corresponding to the pressure protrusion420and the pressure protrusion420corresponding to the insertion groove430are respectively formed, allowing the adjacent lockers400to be coupled to each other.

The plurality of lockers400including the pressure protrusion420and the insertion groove430are configured so that the respective lockers400are mutually coupled to each other. Accordingly, when the locker400is moved adjacent to the internal circumferential surface of the housing100by the magnetic portion440located on the outermost side of at least one locker400, all the lockers400mutually coupled to each other may be integrally moved.

Furthermore, when rotation force of the rotation transmission portion210is applied, the pressure protrusion420applies force to the adjacent locker400in a direction in which the adjacent lockers400respectively contact with the flat surfaces of the output end portion300. In the exemplary embodiment of the present disclosure, when the motor output shaft200is rotated, each surface of the output end portion300including four flat surfaces and each surface of the lockers400are configured to contact with each other.

Therefore, when the opening410of the locker400is pressed by the rotation transmission portion210, the pressure protrusion420of the locker400is inserted into the insertion groove430of the adjacent locker400to be coupled to each other. That is, the pressure protrusion420presses the surface of the adjacent insertion groove430, and the locker400, the surface of which is pressed by the pressure protrusion420, is configured to move the adjacent lockers400in a direction of contacting with a plurality of parallel surfaces of the output end portion300.

In the present manner, when the motor output shaft200is rotated, the locker400presses the lockers400adjacent to each other to apply force in the same direction as the rotation direction thereof. Furthermore, the locker400includes the pressure protrusion420and the insertion groove430to press the adjacent locker400so that the flat surface of the output end portion300and the internal surface of the adjacent locker400contact with each other.

As illustrated inFIG.5D, the locker400contacts with the flat surface of the output end portion300so that the surface of the output end portion300is constrained by the locker400, and when the surfaces of at least some of the lockers400adjacent to each other contact with the output end portion300, the flat surfaces of the output end portion300are located to be in contact with the plurality of lockers400. Furthermore, the internal circumferential surface of the housing100and the external circumferential surface of the locker400are configured to be spaced from each other.

Therefore, torque applied to the rotation transmission portion210of the motor output shaft200is transmitted to the locker400and the output end portion300without interference with the internal circumferential surface of the housing100.

As illustrated inFIG.5E, the motor output shaft200, the plurality of lockers400, and the output end portion300are integrally rotated according to the torque of the motor output shaft200.

Accordingly, the torque of the motor output shaft200is transmitted to the output end portion300corresponding to clockwise rotation in the drawing.

In the present manner, when driving of the motor1510is applied, as illustrated inFIG.4C, rotational torque of the motor output shaft200is applied to the sun gear1521, and torque balance is achieved by the applied torque of the sun gear1521, the reaction torque of the spring portion1530, and the external torque applied from the rod portion1120to the carrier1525.

FIG.6illustrates a driving relationship of the clutch unit10when torque is applied to the output end portion300in a state in which the torque of the motor output shaft200is released.

As illustrated in the drawing, when the output end portion300is rotated, force is provided to push the locker400located adjacent to the output end portion300in the radial direction of the housing100, and the locker400is configured to limit rotation thereof by contacting with the braking portion510located on the internal circumferential surface of the housing100.

That is, torque by the torque applied to the output end portion300applies force to move the locker400in the radial direction of the housing100, and the locker400and the braking portion510are configured to contact with each other according to the applied force. Moreover, the movement of the locker400is limited through magnetic force formed between the magnetic portion440and the steel portion500as well as the torque of the output end portion300. Therefore, the torque applied to the output end portion300is offset by reaction force formed between the braking portion510and the locker400, and the torque introduced from the output end portion300is not transmitted to the motor output shaft200.

That is, when the sun gear1521is rotated to apply torque to the clutch unit10, the locker400configured to surround the output end portion300is located to contact with the braking portion510so that the torque of the output end portion300is not transmitted to the motor output shaft200.

As described above, when the motor1510is not driven, the torque applied to the clutch unit10through the output end portion300of the clutch unit10is not applied to the motor output shaft200by the braking portion510. Therefore, as illustrated inFIG.4D, the torque applied to the reducer through the motor1510and the torque transmitted from the reducer to the motor1510become 0, and new torque balance is achieved based on the reaction force of the spring portion1530located in the reducer and the reaction force applied to the rod portion1120coupled to the carrier. Furthermore, the planetary gear1522and the carrier1525are moved to a location at which the new torque balance is achieved, and the load portion1120is rotated in response to the rotation amount (rotation angle) of the carrier1525, performing control of the vehicle height.

As is apparent from the above description, the present disclosure may obtain the following effects by the above-described configuration, coupling, and use relationship.

Various aspects of the present disclosure are directed to providing a vehicle control system configured to control vehicle height by adjusting input torque of a separate spring reaction force variable device depending on the load state of a vehicle, making it possible to reliably control the vehicle height when a load difference is large.

Furthermore, the amount of motor driving of the spring reaction force variable device and the number of times thereof are controlled to adjust suspension characteristics of a vehicle body generated depending on the driving state of the vehicle, including an effect of simultaneously improving driving stability and ride comfort of the vehicle.

In an exemplary embodiment of the present disclosure, the vehicle may be referred to as being based on a concept including various means of transportation. In some cases, the vehicle may be interpreted as being based on a concept including not only various means of land transportation, such as cars, motorcycles, trucks, and buses, that drive on roads but also various means of transportation such as airplanes, drones, ships, etc.

According to an exemplary embodiment of the present disclosure, components may be combined with each other to be implemented as one, or some components may be omitted.