JP2006007803A - Roll motion control device for vehicle - Google Patents

Abstract

Rolling of a vehicle without deteriorating the ride comfort of the vehicle by appropriately controlling the contribution degree of the two devices to the increase / decrease of the anti-roll moment by utilizing the features of the anti-roll moment increasing / decreasing device and the suspension support rigidity increasing / decreasing device Is effectively reduced.
An increase amount ΔMars of an anti-roll moment by active stabilizer devices 16 and 18 and an increase amount ΔMarp of an anti-roll moment by air springs 24FL to 24RR are calculated based on a lateral acceleration Gy of the vehicle (S20, 40). The active stabilizer devices 16 and 18 are controlled based on ΔMars (S30, 70), the spring constants of the air springs 24FL to 24RR are controlled based on the increase amount ΔMarp (S60, 80), and are large when the lateral acceleration Gy is small. The increase amount ΔMarp is set to be smaller than the increase amount ΔMars (S20, 40).
[Selection] Figure 5

Description

  The present invention relates to a vehicle roll motion control device, and more specifically, suppresses vehicle roll by increasing / decreasing an anti-roll moment by a suspension support rigidity increasing / decreasing device or an anti-roll moment increasing / decreasing device in accordance with the roll degree of the vehicle. The present invention relates to a vehicle roll motion control device.

  As one of roll motion control devices for vehicles such as automobiles, for example, as described in Patent Document 1 below, a two-divided stabilizer, an actuator that relatively rotates a torsion bar of the stabilizer, and a control that controls the actuator In a situation where a high roll moment is applied to the vehicle, such as when the vehicle is turning, the two torsion bars are rotated relative to each other by the actuator to reduce the anti-roll moment applied to the vehicle. Active stabilizer devices configured to increase are known in the art.

According to such an active stabilizer device, the anti-roll moment applied to the vehicle can be increased in a situation where a high roll moment acts on the vehicle, so that the vehicle can be compared with a case where the stabilizer is a normal stabilizer. Thus, it is possible to reduce the roll of the vehicle when turning or the like without deteriorating the ride comfort during the straight traveling, and to improve the steering stability of the vehicle.
Japanese Patent Laid-Open No. 7-40731

  In general, the roll of a vehicle during turning or the like is caused by the amount of elastic deformation of the suspension springs of the left and right wheels being different from each other due to load movement in the left and right direction, and the left and right vehicle heights are different from each other. It is also possible to reduce the roll of the vehicle by increasing the suspension support rigidity, that is, the difficulty of changing the vehicle height with respect to the change in the wheel support load. The suspension support rigidity changes, for example, the spring constant of the suspension spring. Can be increased or decreased.

  Further, an anti-roll moment increasing / decreasing device such as an active stabilizer device can reduce the roll of the vehicle during turning without increasing the suspension support rigidity, in other words, without deteriorating the ride comfort of the vehicle. However, there is a limit to the range of increase / decrease of the anti-roll moment. On the other hand, the suspension support rigidity can be increased or decreased over a wide range, and the roll of the vehicle can be effectively reduced. However, if the suspension support rigidity is increased, the force from the road surface is easily transmitted to the vehicle body via the suspension. As a result, the ride comfort of the vehicle deteriorates.

  In the invention in which the roll of the vehicle is reduced by the anti-roll moment increasing / decreasing device or the suspension support stiffness increasing / decreasing device as in the conventional roll motion control device described above, both the anti-roll moment increasing / decreasing device and the suspension support stiffness increasing / decreasing device are used. In view of the effective reduction of rolls and the features of the two devices, there has not been sufficient study on how to operate these devices, and there is room for improvement in this regard.

  The present invention has been made in view of the above-described current situation in the conventional roll motion control device, and the main problem of the present invention is to make use of the features of the anti-roll moment increasing / decreasing device and the suspension support stiffness increasing / decreasing device. By appropriately controlling the degree of contribution of the two devices to the increase / decrease of the anti-roll moment, the roll of the vehicle is effectively reduced without deteriorating the riding comfort of the vehicle.

  According to the present invention, the main problems described above are the structure of claim 1, that is, a support rigidity increasing / decreasing device that increases / decreases the support rigidity of the suspension provided on each wheel, and an anti-roll moment applied to the vehicle. A vehicle having a roll moment increasing / decreasing device and a roll degree determining means for determining the roll degree of the vehicle, and increasing / decreasing the anti-roll moment by the support rigidity increasing / decreasing device or the anti-roll moment increasing / decreasing device according to the roll degree of the vehicle. A vehicle roll motion control device that suppresses rolls of the vehicle, and when the roll degree of the vehicle is low, the contribution degree of the support rigidity increase / decrease device with respect to increase / decrease of the anti-roll moment is higher than that when the roll degree of the vehicle is high. Having a contribution degree control means for lowering the contribution degree of the roll moment increasing / decreasing device. It is achieved by vehicle roll motion controller according to symptoms.

  According to the present invention, in order to effectively achieve the above main problem, the roll degree determination means determines the roll degree of the vehicle based on the lateral acceleration of the vehicle. (Structure of claim 2).

  Further, according to the present invention, in order to effectively achieve the above-mentioned main problems, in the configuration of the above-described claim 1 or 2, the contribution degree control means is configured such that the vehicle roll degree is less than a reference value when the vehicle roll degree is less than a reference value. It is comprised so that the contribution degree of the said support rigidity increase / decrease apparatus may be made low compared with when a roll degree is more than the said reference value (structure of Claim 3).

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration of the above-described claims 1 to 3, the contribution degree control means is configured so that the vehicle roll degree is less than a reference value. The degree of contribution of the anti-roll moment increasing / decreasing device is controlled according to the degree of roll, and the degree of contribution of the anti-roll moment increasing / decreasing device is maintained substantially constant when the roll degree of the vehicle is equal to or greater than the reference value. (Configuration of claim 4).

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration of claims 1 to 4, the anti-roll moment increasing / decreasing device includes a two-divided stabilizer and a torsion bar of the stabilizer. An active stabilizer having an actuator for relative rotation, and configured to increase or decrease the anti-roll moment by increasing or decreasing the rotation angle of the actuator.

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration of claims 1 to 5, the support rigidity increasing / decreasing device increases or decreases the spring constant of the suspension spring. It is comprised so that support rigidity may be increased / decreased (structure of Claim 6).

  According to the first aspect of the present invention, when the vehicle roll degree is low, the contribution degree of the support rigidity increasing / decreasing device to the increase / decrease of the anti-roll moment is greater than the contribution degree of the anti-roll moment increasing / decreasing device compared to when the vehicle roll degree is high. Therefore, compared with the case where the contribution degree of the support rigidity increasing / decreasing device is high, the degree to which the force from the road surface is transmitted to the vehicle body via the suspension is reduced, thereby ensuring good riding comfort of the vehicle. In addition, the degree of contribution of the anti-roll moment increasing / decreasing device can be increased to effectively reduce the roll of the vehicle when turning.

  According to the configuration of the second aspect, since the roll degree of the vehicle is determined based on the lateral acceleration of the vehicle, it is possible to determine the lateral force acting on the vehicle and the degree of vehicle roll caused by the lateral force. Thus, the anti-roll moment can be increased or decreased according to the degree of rolling of the vehicle.

  According to the third aspect of the present invention, when the roll degree of the vehicle is less than the reference value, the contribution degree of the support rigidity increasing / decreasing device is made lower than when the vehicle roll degree is greater than the reference value. In a situation where the degree of the vehicle is low and the ride comfort of the vehicle should be given priority, it is possible to ensure the good ride comfort of the vehicle.

  Further, according to the configuration of claim 4, when the roll degree of the vehicle is less than the reference value, the contribution degree of the anti-roll moment increasing / decreasing device is controlled according to the roll degree of the vehicle, and the roll degree of the vehicle is equal to or higher than the reference value. Sometimes, the degree of contribution of the anti-roll moment increasing / decreasing device is maintained substantially constant, so when the vehicle roll degree is less than a reference value, the anti-roll moment increasing / decreasing device increases / decreases according to the degree of rolling of the vehicle. In addition, it is not necessary for the anti-roll moment increasing / decreasing device to apply a high anti-roll moment to the vehicle, thereby avoiding the need for a high-power device as the anti-roll moment increasing / decreasing device.

  According to the configuration of claim 5, the anti-roll moment increasing / decreasing device includes an active stabilizer having a two-divided stabilizer and an actuator that relatively rotates the torsion bar of the stabilizer, and the anti-roll moment is increased by increasing / decreasing the rotation angle of the actuator. Since it is increased / decreased, the anti-roll moment by the anti-roll moment increasing / decreasing device can be reliably increased / decreased.

  According to the sixth aspect of the present invention, since the suspension support rigidity is increased or decreased by increasing or decreasing the spring constant of the suspension spring, the suspension support rigidity can be reliably increased or decreased.

[Preferred embodiment of problem solving means]
According to one preferable aspect of the present invention, in the configuration of the above first to sixth aspects, the contribution degree control means increases or decreases the support rigidity when the vehicle roll degree is high compared to when the vehicle roll degree is low. Increase or decrease the anti-roll moment by the support rigidity increasing / decreasing device or the anti-roll moment increasing / decreasing device according to the rolling degree of the vehicle so that the sum of the anti-roll moment by the device and the anti-roll moment increasing / decreasing device by the device becomes a large value. (Preferred embodiment 1).

  According to another preferred aspect of the present invention, in the configurations of 1 to 6 and preferred aspect 1, the contribution degree control means is configured to increase the anti-roll moment target by the support rigidity increasing / decreasing device based on the roll degree of the vehicle. It is comprised so that the target increase amount of the anti-roll moment by a mass and anti-roll moment increase / decrease apparatus may be calculated (Preferred aspect 2).

  According to another preferred embodiment of the present invention, in the configuration of the preferred embodiment 2, the contribution degree control means is configured to increase the target anti-roll moment by the support rigidity increasing / decreasing device when the roll degree of the vehicle is less than the reference value. By calculating a large amount to a value smaller than the target increase amount of the anti-roll moment by the anti-roll moment increasing / decreasing device, the anti-roll moment can be reduced when the vehicle roll degree is low compared to when the vehicle roll degree is high. It is comprised so that the contribution degree of the support rigidity increase / decrease apparatus with respect to increase / decrease may be made lower than the contribution degree of an anti-roll moment increase / decrease apparatus (Preferable aspect 3).

  According to another preferred aspect of the present invention, in the configuration of the preferred aspect 2 or 3, the contribution degree control means is configured so that the target increase amount of the anti-roll moment by the support rigidity increasing / decreasing device of the front wheel is the support rigidity of the rear wheel. The target increase amount of the anti-roll moment by the support rigidity increasing / decreasing device for the front wheels and the rear wheel is calculated so as to be larger than the target increase amount of the anti-roll moment by the increasing / decreasing device (Preferred aspect 4).

  According to another preferred embodiment of the present invention, in the configurations of the preferred embodiments 2 to 4, the anti-roll moment increasing / decreasing device includes an anti-roll moment increasing / decreasing device on the front wheel side and an anti-roll moment increasing / decreasing device on the rear wheel side. The contribution degree control means is configured so that the target increase amount of the anti-roll moment by the anti-roll moment increasing / decreasing device on the front wheel side is larger than the target increase amount of the anti-roll moment by the anti-roll moment increasing / decreasing device on the rear wheel side. A target increase amount of the anti-roll moment by the wheel-side anti-roll moment increasing / decreasing device is calculated (preferred aspect 5).

  According to another preferred aspect of the present invention, in the configuration of claim 2, the roll degree determination means detects the lateral acceleration of the vehicle, and the roll degree of the vehicle is detected based on the detected lateral acceleration of the vehicle. Is determined (preferred aspect 6).

  According to another preferred aspect of the present invention, in the configuration of claim 2, the roll degree determination means estimates the lateral acceleration of the vehicle based on the vehicle speed and the steering angle, and the estimated lateral acceleration of the vehicle is calculated. It is comprised so that the roll degree of a vehicle may be determined based on (The preferable aspect 7).

  According to another preferred aspect of the present invention, in the configuration of claim 2, the roll degree determination means detects the lateral acceleration of the vehicle and estimates the lateral acceleration of the vehicle based on the vehicle speed and the steering angle. The roll degree of the vehicle is determined based on the estimated lateral acceleration of the vehicle and the estimated lateral acceleration of the vehicle (preferred aspect 8).

  According to another preferred aspect of the present invention, in the configuration of claim 3, the contribution degree control means sets the contribution degree of the support rigidity increasing / decreasing device to 0 when the roll degree of the vehicle is less than a reference value. (Preferred embodiment 9).

  According to another preferred aspect of the present invention, in the configuration of claim 3 or 4, the contribution degree control means is configured such that when the roll degree of the vehicle is less than a reference value, the roll degree of the vehicle is greater than or equal to the reference value. The contribution degree of the support rigidity increasing / decreasing device is lower than that of the vehicle, and when the roll degree of the vehicle is less than the reference value, the contribution degree of the anti-roll moment increasing / decreasing device is controlled according to the roll degree of the vehicle, and the roll degree of the vehicle is the reference When the value exceeds the value, the contribution degree of the anti-roll moment increasing / decreasing device is maintained substantially constant, and the increase rate of the contribution degree of the supporting rigidity increasing / decreasing device accompanying the increase of the vehicle roll degree is to increase the absolute value of the lateral acceleration of the vehicle. It is comprised so that it may be larger than the increase rate of the contribution degree of the accompanying anti-roll moment increasing / decreasing apparatus (preferable aspect 10).

  According to another preferred aspect of the present invention, in the structure of claim 3 or 4, the reference value can be changed by setting means operated by a vehicle occupant (preferred aspect 11). ).

  According to another preferred aspect of the present invention, in the structure of claim 6, the suspension spring is configured to be an air spring having means for increasing or decreasing the volume or pressure of the air chamber (preferred aspect 12). ).

  According to another preferred aspect of the present invention, in each of the first to sixth aspects, the suspension of each wheel has a shock absorber with a variable damping coefficient, and the damping coefficient is increased or decreased during a transient turning of the vehicle. By doing so, the support rigidity of the suspension is increased or decreased (preferred aspect 13).

  The present invention will now be described in detail with reference to a few preferred embodiments with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing an embodiment of a vehicle roll motion control device according to the present invention applied to a vehicle in which active stabilizer devices are provided on the front wheel side and the rear wheel side and the suspension of each wheel is an air suspension with a variable spring constant. It is a block diagram.

  In FIG. 1, 10 FL and 10 FR respectively indicate left and right front wheels that are driven wheels of the vehicle 12, and 10 RL and 10 RR respectively indicate left and right rear wheels that are drive wheels of the vehicle 12. The left and right front wheels 10FL and 10FR, which are also steered wheels, are steered via tie rods by a power steering device (not shown) that is driven in response to steering of the steering wheel 14 by the driver.

  An active stabilizer device 16 is provided between the left and right front wheels 10FL and 10FR, and an active stabilizer device 18 is provided between the left and right rear wheels 10RL and 10RR. The active stabilizer devices 16 and 18 function as an anti-roll moment increasing / decreasing device that applies an anti-roll moment to the vehicle (vehicle body) and increases / decreases the anti-roll moment as necessary.

  The active stabilizer device 16 is integrally connected to a pair of torsion bar portions 16TL and 16TR extending coaxially with each other along an axis extending in the lateral direction of the vehicle, and to the outer ends of the torsion bar portions 16TL and 16TR, respectively. And a pair of arm portions 16AL and 16AR. The torsion bar portions 16TL and 16TR are supported by a vehicle body not shown in the drawing via brackets not shown in the drawing so as to be rotatable around their own axes. The arm portions 16AL and 16AR extend in the longitudinal direction of the vehicle so as to intersect the torsion bar portions 16TL and 16TR, respectively, and the outer ends of the arm portions 16AL and 16AR are respectively left and right through rubber bush devices not shown in the drawing. The front wheels 10FL and 10FR are connected to wheel support members or suspension arms.

  The active stabilizer device 16 has an actuator 20F between the torsion bar portions 16TL and 16TR. The actuator 20F rotates the pair of torsion bar portions 16TL and 16TR in opposite directions as necessary, so that when the left and right front wheels 10FL and 10FR bounce and rebound in opposite phases, the wheel bounces due to torsional stress. By changing the force to suppress rebound, the anti-roll moment applied to the vehicle at the positions of the left and right front wheels is increased or decreased, and the roll rigidity of the vehicle on the front wheel side is variably controlled.

  Similarly, the active stabilizer device 18 has a pair of torsion bar portions 18TL and 18TR extending coaxially with each other along an axis extending in the lateral direction of the vehicle, and the outer ends of the torsion bar portions 18TL and 18TR, respectively. It has a pair of arm portions 18AL and 18AR connected together. The torsion bar portions 18TL and 18TR are respectively supported by a vehicle body not shown in the drawing via brackets not shown in the drawing so as to be rotatable around their own axes. The arm portions 18AL and 18AR extend in the longitudinal direction of the vehicle so as to intersect the torsion bar portions 18TL and 18TR, respectively, and the outer ends of the arm portions 18AL and 18AR are respectively left and right through rubber bushing devices not shown in the drawing. The rear wheels 10RL and 10RR are connected to wheel support members or suspension arms.

  The active stabilizer device 18 has an actuator 20R between the torsion bar portions 18TL and 18TR. The actuator 20R rotates the pair of torsion bar portions 18TL and 18TR in directions opposite to each other as necessary, so that when the left and right rear wheels 10RL and 10RR bounce and rebound in opposite phases, the torsional stress causes the wheel By changing the force to suppress bounce and rebound, the anti-roll moment applied to the vehicle at the positions of the left and right rear wheels is increased or decreased, and the roll rigidity of the vehicle on the rear wheel side is variably controlled.

  Since the structures of the active stabilizer devices 16 and 18 do not form the gist of the present invention, any structure known in the art can be used as long as the roll rigidity of the vehicle can be variably controlled. However, for example, the active stabilizer device described in Japanese Patent Application No. 2003-324212 (reference number AT-5552) specification and drawings relating to the application of the present applicant, that is, a drive gear fixed to the inner end of one torsion bar portion is provided. An electric motor having an attached rotating shaft and a driven gear that is fixed to the inner end of the other torsion bar portion and meshes with the driving gear. The driving gear and the driven gear transmit the rotation of the driving gear to the driven gear. The active stabilizer device is preferably a gear that does not transmit the rotation of the driven gear to the drive gear.

  In the illustrated embodiment, the suspensions 22FL and 22FR of the left and right front wheels 10FL and 10FR are variable spring constant air suspensions having air springs 24FL and 24FR, respectively. Similarly, the suspensions 22RL and 22RR of the left and right rear wheels 10RL and 10RR are variable spring constant type air suspensions having air springs 24RL and 24RR, respectively.

  For example, as shown in FIG. 2 for the air spring 24FL of the left front wheel, the air springs 24FL, 24FR, 24RL, 24RR are supported by the piston rod 26Ai of the shock absorber 26i (i = fl, fr, rl, rr) or the vehicle body. And a rolling diaphragm 30i provided between the chamber member 28i and the cylinder 26Bi of the shock absorber 26i, thereby defining an air chamber 32i.

  A cylinder chamber 36i of a cylinder-piston device 34i is connected to the air chamber 32i, and a piston 38i of the cylinder-piston device 34i is driven by a reciprocating actuator 40i. Accordingly, the volume of the cylinder chamber 36i is increased or decreased by the reciprocation of the piston 38i, whereby the total volume of the air chamber 32i and the cylinder chamber 36i is increased or decreased, and the pressure in the air chamber 32i and the cylinder chamber 36i is reduced. As a result, the spring constant Ki of the air springs 24FL to 24RR is decreased or increased stepwise or continuously.

  The actuators 20F and 20R of the active stabilizer devices 16 and 18 are controlled by the electronic control device 42, and the actuators 40i of each wheel are controlled by the electronic control device 44. Although not shown in detail in FIG. 1, each of the electronic control devices 42 and 44 has a CPU, a ROM, a RAM, and an input / output port device, which are connected to each other by a bidirectional common bus. And a drive circuit.

  As shown in FIG. 1, the electronic control unit 42 includes a signal indicating the vehicle lateral acceleration Gy detected by the lateral acceleration sensor 50 and the actual rotation of the actuators 20F and 20R detected by the rotation angle sensors 52F and 52R. Signals indicating the angles φF and φR are input. The electronic control units 42 and 44 communicate with each other and exchange necessary signals. The lateral acceleration sensor 50 and the rotation angle sensors 52F and 52R detect the lateral acceleration Gy and the rotation angles φF and φR, respectively, with the value generated when the vehicle turns to the left as positive.

  The electronic control unit 42 stores a map corresponding to the graph shown in FIG. 4 and a control routine according to the flowchart shown in FIG. 5, and is activated based on the vehicle lateral acceleration Gy which is an index value of the vehicle roll degree. The amount of increase ΔMars of the anti-roll moment by the stabilizer devices 16 and 18 is calculated, and the actuator 20F of the active stabilizer devices 16 and 18 based on the amount of increase ΔMars so as to increase the anti-roll moment in the direction to cancel the roll moment acting on the vehicle. The target rotation angles φFt and φRt of 20R are calculated and controlled so that the rotation angles φF and φR of the actuators 20F and 20R correspond to the corresponding target rotation angles φFt and φRt, respectively. To reduce.

  Therefore, the active stabilizer devices 16 and 18, the electronic control device 42, the lateral acceleration sensor 50, etc. function as an anti-roll moment increasing / decreasing device that increases the anti-roll moment and reduces the roll of the vehicle when an excessive roll moment acts on the vehicle. To do.

  Further, the electronic control unit 26 calculates the anti-roll moment increase amount ΔMarp by the air springs 24FL to 24RR based on the lateral acceleration Gy of the vehicle according to the control routine according to the flowchart shown in FIG. 5, and based on the increase amount ΔMarp, The anti-roll moment increase amount ΔMarpf by the air springs 24FL and 24FR and the anti-roll moment increase amount ΔMarpr by the left and right rear wheel air springs 24RL and 24RR are calculated, and based on the increase amount ΔMarpf and the increase amount ΔMarpr, the air spring 24FL of each wheel A target spring constant Kti of ˜24RR is calculated, and a signal indicating the target spring constant Kti is output to the electronic control unit 44.

  The electronic control unit 44 stores a map corresponding to the graph shown in FIG. 3 and a control routine according to the flowchart shown in FIG. 6, and a command signal indicating the target spring constant Kti is input from the electronic control unit 42. When there is not, control is performed so that the spring constant Ki of the air springs 24FL to 24RR of each wheel becomes the standard spring constant Ko (positive constant), but when the command signal indicating the target spring constant Kti is input from the electronic control unit 42. Control is performed so that the spring constants Ki of the air springs 24FL to 24RR of the respective wheels become the corresponding target spring constants Kti, thereby increasing the anti-roll moment and reducing the roll of the vehicle when an excessive roll moment acts on the vehicle. To do.

  Next, the roll control routine in the embodiment will be described with reference to the flowchart shown in FIG. The control according to the flowchart shown in FIG. 5 is started by closing an ignition switch (not shown), and is repeatedly executed at predetermined time intervals.

  First, in step 10, the vehicle lateral acceleration Gy detected by the lateral acceleration sensor 50 is read, and in step 20, the graph shown by the solid line in FIG. 4 based on the vehicle lateral acceleration Gy. The amount of increase ΔMars of the anti-roll moment by the active stabilizer devices 16 and 18 is calculated from the map corresponding to.

In step 30, for example, the front wheel distribution ratio of the increase amount ΔMars of the anti-roll moment is set to Ksf (a positive constant larger than 0.5 and smaller than 1) by the active stabilizer device 16 on the front wheel side based on the increase amount ΔMars. The increase amount ΔMarsf of the anti-roll moment and the increase amount ΔMarsr of the anti-roll moment by the active stabilizer device 18 on the rear wheel side are calculated according to the following equations 1 and 2, respectively, and based on the increase amounts ΔMarsf and ΔMarsr, respectively, by a function or a map Target rotation angles φFt and φRt of the actuators 20F and 20R of the active stabilizer devices 16 and 18 are calculated.
ΔMarsf = KsfΔMars (1)
ΔMarsr = (1−Ksf) ΔMars (2)

  In step 40, based on the lateral acceleration Gy of the vehicle, an anti-roll moment increase amount ΔMarp by the air springs 24FL to 24RR is calculated from a map corresponding to the graph shown by the broken line in FIG.

In step 50, for example, assuming that the front wheel distribution ratio of the increase amount ΔMarp of the anti-roll moment is Kpf (a positive constant larger than 0.5 and smaller than 1), the air springs 24FL and 24FR of the left and right front wheels are based on the increase amount ΔMarp. The anti-roll moment increase amount ΔMarpf by the left and right rear wheel air springs 24RL and 24RR is calculated according to the following equations 3 and 4, respectively.
ΔMarpf = KpfΔMarp (3)
ΔMarpr = (1−Kpf) ΔMarp (4)

  In step 60, the turning direction of the vehicle is determined based on the lateral acceleration Gy of the vehicle, and the target spring constant Ktfl or Ktfr of the air spring 24FL or 24FR of the outer front wheel is calculated from a function or map based on the increase amount ΔMarpf. Based on the increase amount ΔMarpr, the target spring constant Ktrl or Ktrr of the air spring 24RL or 24RR of the turning outer rear wheel is calculated by a function or a map. The target spring constant of the turning inner front wheel and the turning inner rear wheel is set to the standard value Ko.

  In step 70, the rotation angles φF and φR of the actuators 20F and 20R are controlled to the corresponding target rotation angles φFt and φRt, respectively. In step 80, the target spring constants of the air springs 24FL to 24RR of each wheel are controlled. A signal indicating Kti is output to the electronic control unit 44.

  Next, the spring constant control routine of the air spring in the embodiment will be described with reference to the flowchart shown in FIG. Note that the control according to the flowchart shown in FIG. 6 is also started by closing an ignition switch (not shown), and is repeatedly executed every predetermined time.

  First, in step 110, it is determined whether or not a signal indicating the target spring constant Kti is input from the electronic control unit 42. If an affirmative determination is made, the process proceeds to step 140, and if a negative determination is made. In step 120, the target drive amount Sti (i = fl, fr, rl, rr) of the actuator 40 of the air spring 24FL, 24FR, 24RL, 24RR of each wheel is set to zero.

  In step 140, the target spring constants Kti (i = fl, fr, rl, rr) of the air springs 24FL, 24FR, 24RL, 24RR of each wheel are set to the values input from the electronic control unit 42, and step 150 In this case, based on the target spring constant Kti, the target drive amount Sti (i = fl, fr, rl) of the actuator 40 of the air springs 24FL, 24FR, 24RL, 24RR of each wheel is determined from the map corresponding to the graph shown in FIG. , Rr) is calculated.

  In step 160, the actuators 40 of the air springs 24FL to 24RR of the respective wheels are controlled based on the target drive amount Sti, thereby controlling the spring constants of the air springs 24FL to 24RR to the corresponding target spring constants Kti. Is done.

  Thus, according to the illustrated embodiment, in step 20, the amount of increase ΔMars of the anti-roll moment by the active stabilizer devices 16 and 18 is calculated based on the lateral acceleration Gy of the vehicle, and in step 30, the front wheels are calculated based on the amount of increase ΔMars. The increase amount ΔMarsf of the anti-roll moment by the active stabilizer device 16 on the side and the increase amount ΔMarsr of the anti-roll moment by the active stabilizer device 18 on the rear wheel side are calculated, and based on the increase amounts ΔMarsf and ΔMarsr, respectively, The target rotation angles φFt and φRt of the 18 actuators 20F and 20R are calculated, and in step 70, the rotation angles φF and φR of the actuators 20F and 20R are controlled to the corresponding target rotation angles φFt and φRt, respectively.

  In step 40, the amount of increase ΔMarp of the anti-roll moment by the air springs 24FL to 24RR is calculated based on the lateral acceleration Gy of the vehicle indicating the degree of roll of the vehicle. In step 50, the air in the left and right front wheels is calculated based on the amount of increase ΔMarp. The anti-roll moment increase amount ΔMarpf by the springs 24FL and 24FR and the anti-roll moment increase amount ΔMarpr by the left and right rear wheel air springs 24RL and 24RR are calculated, and in step 60, the air spring of the outer front wheel is turned based on the increase amount ΔMarpf. The target spring constant Ktfl or Ktfr of 24FL or 24FR is calculated, and the target spring constant Ktrl or Ktrr of the rear outer wheel air spring 24RL or 24RR is calculated based on the increase amount ΔMarpr. In step 80, the air spring of each wheel is calculated. The target spring constant Kti of 24FL to 24RR is shown. A signal is output to the electronic control unit 44.

  In step 140 of the routine shown in FIG. 6, the target spring constants Kti of the air springs 24FL, 24FR, 24RL, and 24RR for each wheel are set to the values input from the electronic control unit 42, and in step 150. Based on the target spring constant Kti, the target drive amount Sti of the actuator 40 of the air springs 24FL, 24FR, 24RL, 24RR of each wheel is calculated, and in step 160, the actuator 40 of the air springs 24FL-24RR of each wheel is the target drive amount. Based on Sti, the spring constants of the air springs 24FL to 24RR are controlled to become the corresponding target spring constants Kti.

  As shown in FIG. 4, the increase amount ΔMars of the anti-roll moment by the active stabilizer devices 16 and 18 is the absolute value of the lateral acceleration Gy of the vehicle when the absolute value of the lateral acceleration Gy of the vehicle is less than the reference value Gyo. As the value increases, the value gradually increases, and the absolute value of the lateral acceleration Gy of the vehicle is kept constant in the range of the reference value Gyo or more. On the other hand, the increase amount ΔMarp of the anti-roll moment by the air springs 24FL to 24RR is maintained at 0 when the absolute value of the lateral acceleration Gy of the vehicle is less than the reference value Gyo, and the absolute value of the lateral acceleration Gy of the vehicle is the reference value. In the range above Gyo, it gradually increases as the absolute value of the lateral acceleration Gy of the vehicle increases.

  Therefore, according to the illustrated embodiment, when the absolute value of the lateral acceleration Gy of the vehicle is less than the reference value Gyo, the anti-roll moment is increased by the active stabilizer devices 16 and 18, and the spring constants of the air springs 24FL to 24RR are increased. Since Ki is maintained at the standard value Ko, it is possible to effectively reduce the roll of the vehicle by increasing the anti-roll moment by the active stabilizer devices 16 and 18, and to improve the running stability of the vehicle when turning. In addition, it is possible to reliably prevent the deterioration of the riding comfort of the vehicle due to the increase in the spring constant of the air spring of each wheel.

  Further, according to the embodiment shown in the figure, in the range where the absolute value of the lateral acceleration Gy of the vehicle is equal to or larger than the reference value Gyo, the increase amount ΔMars of the anti-roll moment by the active stabilizer devices 16 and 18 is kept constant. The active stabilizer devices 16 and 18 need not generate very large anti-roll moments, thereby eliminating the need for the active stabilizer devices 16 and 18 to be high power devices.

  Particularly, according to the illustrated embodiment, the front wheel distribution ratio Ksf of the anti-roll moment increase amount ΔMars and the front wheel distribution ratio Kpf of the anti-roll moment increase amount ΔMarp are positive constants greater than 0.5 and smaller than 1. Since the amount of increase in the anti-roll moment on the front wheel side is larger than that on the rear wheel side, the roll stiffness distribution of the vehicle is made closer to the front wheel as the anti-roll moment increases, thereby improving the running stability of the vehicle when turning be able to.

  Further, according to the illustrated embodiment, the increase amount ΔMarp of the anti-roll moment by the air springs 24FL to 24RR is the absolute value of the lateral acceleration Gy of the vehicle in the range where the absolute value of the lateral acceleration Gy of the vehicle is equal to or larger than the reference value Gyo. Since it gradually increases as it increases, the roll amount of the vehicle is surely and effectively reduced even when the anti-roll moment increase amount ΔMars by the active stabilizer devices 16 and 18 is maintained constant. The running stability of the vehicle in the vehicle can be improved reliably and effectively.

  Further, according to the illustrated embodiment, the increase rate of the anti-roll moment increase amount ΔMarp due to the air springs 24FL to 24RR accompanying the increase in the absolute value of the vehicle lateral acceleration Gy is accompanied by the increase in the absolute value of the vehicle lateral acceleration Gy. Since the increase rate of the increase amount ΔMars of the anti-roll moment by the active stabilizer devices 16 and 18 is larger, the magnitude of the lateral acceleration Gy of the vehicle is smaller than when the magnitude relationship between these increase rates is the same or opposite. It is possible to surely and effectively reduce the roll of the vehicle in the region where the magnitude of the lateral acceleration Gy of the vehicle is large while ensuring good riding comfort of the vehicle in the small region.

  Although the present invention has been described in detail with reference to specific embodiments, the present invention is not limited to the above-described embodiments, and various other embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art.

  For example, in the above-described embodiment, the roll degree of the vehicle is the lateral acceleration Gy of the vehicle, but the roll degree of the vehicle is the estimated lateral acceleration Gyh of the vehicle calculated based on the vehicle speed V and the steering angle θ. For example, it may be a linear sum of the lateral acceleration Gy of the vehicle and the estimated lateral acceleration Gyh of the vehicle.

  In the above-described embodiment, the increase amount ΔMars of the anti-roll moment by the active stabilizer devices 16 and 18 and the increase amount ΔMarp of the anti-roll moment by the air springs 24FL to 24RR increase the absolute value of the lateral acceleration Gy of the vehicle. As shown in FIG. 7, for example, the increase amount ΔMars or the increase amount ΔMarp increases nonlinearly as the absolute value of the lateral acceleration Gy of the vehicle increases. It may be corrected to do (Modification Example 1).

  In the above embodiment, the anti-roll moment increase amount ΔMars by the active stabilizer devices 16 and 18 and the anti-roll moment increase amount ΔMarp by the air springs 24FL to 24RR are shown by the solid line and the broken line in FIG. 4, respectively. For example, when the setting switch 56 indicated by the phantom line in FIG. 1 and operated by the vehicle occupant is at the steering stability priority position, the map is increased. When the large amount ΔMars and the increase amount ΔMarp are calculated from the map corresponding to the graph shown by the thick solid line and the broken line in FIG. 8 and the setting switch 56 is in the riding comfort priority position, the increase amount ΔMars and the increase amount ΔMarp are It may be modified so as to be calculated from a map corresponding to a graph indicated by 8 thin solid lines and broken lines (Modification Example 2). ).

  In the second modification, the reference value Gyo is the absolute value of the lateral acceleration Gy of the vehicle when the setting switch 56 is in the ride comfort priority position, compared to when the setting switch 56 is in the steering stability priority position. It may be changed to the larger side.

  In the above-described embodiment, the target spring constant Kti of the air springs 24FL to 24RR of the turning outer wheel is higher than the standard value Ko in the range where the absolute value of the lateral acceleration Gy of the vehicle is not less than the reference value Gyo. The increase amount ΔMarp is achieved by setting, but the target spring constant Kti of the air springs 24FL to 24RR of the turning outer ring is set higher than the standard value Ko and the air springs 24FL to 24 of the turning inner ring are set. It may be modified so that the increase amount ΔMarp is achieved by setting the target spring constant Kti of 24RR to be lower than the standard value Ko.

  In the above-described embodiment, the suspension is an air suspension, and the spring constants of the air springs 24FL to 24RR are increased or decreased by increasing or decreasing the volume of the cylinder chamber 36i of the cylinder-piston device 34i connected to the air chamber 32i. Ki is increased or decreased stepwise or continuously, but a plurality of tanks having different volumes are provided, and the communication and blocking of each tank with respect to the air chamber 32i are controlled, whereby the spring constant of the air spring is controlled. May be increased or decreased.

  Further, the roll motion control device of the present invention may be applied to a vehicle having a suspension other than an air suspension, and the suspension is, for example, as long as the support rigidity of each wheel can be adjusted by increasing or decreasing the spring constant of the suspension spring of each wheel. Any suspension known in the art, such as a hydropneumatic suspension, may be used, and the damping coefficient of the shock absorber may be increased or decreased during a transient turning of the vehicle.

FIG. 2 is a schematic configuration diagram showing an embodiment of a vehicle roll motion control device according to the present invention applied to a vehicle in which active stabilizer devices are provided on the front wheel side and the rear wheel side and the suspension of each wheel is a spring constant variable type air suspension. is there. It is explanatory drawing which shows the air spring of the left front wheel shown by FIG. It is a graph which shows the relationship between the target spring constant Kti of an air spring and the target drive amount Sti of the actuator of an air spring. 6 is a graph showing a relationship between a lateral acceleration Gy of a vehicle and an increase amount ΔMars of an anti-roll moment by an active stabilizer device and an increase amount ΔMarp of an anti-roll moment by an air spring in an embodiment. It is a flowchart which shows the roll control routine in an Example. It is a flowchart which shows the spring constant control routine of the air spring in an Example. It is a graph which shows the relationship between lateral acceleration Gy of the vehicle in the modification 1, and the increase amount ΔMars of the anti-roll moment by the active stabilizer device and the increase amount ΔMarp of the anti-roll moment by the air spring. It is a graph which shows the relationship between the lateral acceleration Gy of the vehicle in the modification 2, and the increase amount ΔMars of the anti-roll moment by the active stabilizer device and the increase amount ΔMarp of the anti-roll moment by the air spring.

Explanation of symbols

16, 18 Active stabilizer device 20F, 20R Actuator 24FL-24RR Air spring 32i Air chamber 40i Actuator 42, 44 Electronic control device 50 Lateral acceleration sensor 52F, 52R Rotation angle sensor

Claims (6)

  A support rigidity increasing / decreasing device provided on each wheel for increasing / decreasing the suspension rigidity of the suspension, an anti-roll moment increasing / decreasing device for increasing / decreasing the anti-roll moment applied to the vehicle, and a roll degree determining means for determining the roll degree of the vehicle. A roll motion control device for a vehicle that suppresses the roll of the vehicle by increasing or decreasing the anti-roll moment by the support rigidity increasing / decreasing device or the anti-roll moment increasing / decreasing device according to the roll degree of the vehicle, wherein the roll degree of the vehicle is And a contribution degree control means for lowering the contribution degree of the support rigidity increasing / decreasing device to increase / decrease in anti-roll moment when the vehicle roll degree is lower than when the vehicle roll degree is higher than the contribution degree of the anti-roll moment increasing / decreasing device. A rolling motion control device for a vehicle characterized by the above.   2. The vehicle roll motion control device according to claim 1, wherein the roll degree determination means determines the roll degree of the vehicle based on a lateral acceleration of the vehicle.   2. The contribution degree control means lowers the contribution degree of the support rigidity increasing / decreasing device when the roll degree of the vehicle is less than a reference value as compared with when the roll degree of the vehicle is equal to or more than the reference value. Or a roll motion control device for a vehicle according to 2;   The contribution degree control means controls the contribution degree of the anti-roll moment increasing / decreasing device according to the roll degree of the vehicle when the roll degree of the vehicle is less than the reference value. 4. The vehicle roll motion control device according to claim 1, wherein the contribution degree of the roll moment increasing / decreasing device is maintained substantially constant.   The anti-roll moment increasing / decreasing device includes an active stabilizer having a two-divided stabilizer and an actuator that relatively rotates a torsion bar of the stabilizer, and increases / decreases the anti-roll moment by increasing / decreasing the rotation angle of the actuator. Item 5. A rolling motion control device for a vehicle according to any one of Items 1 to 4. 6. The vehicle roll motion control device according to claim 1, wherein the support stiffness increasing / decreasing device increases / decreases the support stiffness of the suspension by increasing / decreasing a spring constant of the suspension spring.

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