JP2005349981A - Rolling motion control device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress increase of rolling of a vehicle and reduction of operation stability of the vehicle accompanying therewith when abnormality is generated on an anti-rolling moment increase/reduction device. <P>SOLUTION: The rolling motion control device for the vehicle has active stabilizer devices 16, 18 functioned as the anti-rolling moment increase/reduction device for increasing anti-rolling moment and reducing the rolling of the vehicle when the rolling moment is applied to the vehicle. It is determined that abnormality capable of only generating smaller anti-rolling moment than a value to be generated is generated on the anti-rolling moment increase/reduction device based on size or the like of deviation of a target rotation angle and an actual rotation angle of an actuator of the active stabilizer device (S20, 60, 70, 80). When the anti-rolling moment increase/reduction device is abnormal, vehicle height is reduced to the lowermost vehicle height by a vehicle height adjustment device to reduce the rolling moment applied to the vehicle (S170-200). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle roll motion control device, and more particularly, to a vehicle roll motion control device having an anti-roll moment increasing / decreasing device that increases the anti-roll moment and reduces the roll of the vehicle when a roll moment acts on the vehicle. Related to the 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, since the anti-roll moment applied to the vehicle can be increased in a situation where a high roll moment acts on the vehicle, the vehicle can be compared with a case where the stabilizer is a normal stabilizer. It is possible to reduce the roll of the vehicle at the time of turning without deteriorating the riding comfort during the straight traveling of the vehicle and to improve the steering stability of the vehicle.
JP-A-9-123728

  However, in the conventional roll motion control device as described above, if an abnormality that can only generate an anti-roll moment smaller than a value that should occur due to an actuator failure or the like occurs in the active stabilizer device, the active stabilizer device is normal. The roll of the vehicle at the time of turning becomes larger than that of the situation and the steering stability of the vehicle is lowered. This problem is particularly noticeable when an abnormality occurs in the active stabilizer device in a situation where the vehicle has a vehicle height adjusting device and the vehicle height is adjusted to be high by the vehicle height adjusting device.

  The present invention has been made in view of the above-described problems in the conventional roll motion control device having an anti-roll moment increasing / decreasing device that increases the anti-roll moment and reduces the roll of the vehicle when the roll moment acts on the vehicle. Therefore, the main problem of the present invention is that when an abnormality in which the anti-roll moment cannot be sufficiently increased occurs in the anti-roll moment increasing / decreasing device, the roll moment acting on the vehicle is reduced, thereby reducing the anti-roll moment increasing / decreasing. It is to suppress the increase in the roll of the vehicle and the accompanying decrease in the steering stability of the vehicle when an abnormality occurs in the apparatus.

  According to the present invention, the main problem described above is that a vehicle having an anti-roll moment increasing / decreasing device that reduces the roll of a vehicle by increasing the anti-roll moment when a roll moment acts on the vehicle. An abnormality determining means for determining that an abnormality that can only generate an anti-roll moment smaller than a value to be generated has occurred in the anti-roll moment increasing / decreasing device, and the anti-roll moment increasing / decreasing device This is achieved by a vehicle roll motion control device comprising vehicle height control means for reducing the vehicle height when the vehicle is abnormal.

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration of claim 1, the abnormality determining means detects the estimated lateral acceleration and lateral acceleration of the vehicle based on the vehicle speed and the steering angle. The anti-roll moment increasing / decreasing device is determined to be abnormal when the magnitude of the deviation from the lateral acceleration of the vehicle detected by the means is equal to or greater than the lateral acceleration reference value (configuration of claim 2).

  According to the present invention, in order to effectively achieve the main problems described above, in the configuration of claim 1, the anti-roll moment increasing / decreasing device relatively rotates the two-part stabilizer and the torsion bar of the stabilizer. And determining whether the anti-roll moment increasing / decreasing device is abnormal when the magnitude of the deviation between the target rotation angle of the actuator and the actual rotation angle is equal to or greater than a rotation angle reference value. (Structure of claim 3).

  According to the present invention, in order to effectively achieve the main problems described above, the vehicle height control means according to any one of claims 1 to 3 includes front vehicle height control means and rear wheel vehicle height. The control means is configured to reduce the vehicle height on the front wheel side before the vehicle height on the rear wheel side when an abnormality occurs in the anti-roll moment increasing / decreasing device (configuration of claim 4).

  Further, according to the present invention, in order to effectively achieve the above main problem, at least the front wheel side vehicle height control means can supply and discharge high pressure air to the air chamber. It is comprised so that it may be an air spring (structure of Claim 5).

  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 5, the vehicle height control means is provided for a fluid chamber provided corresponding to each wheel. Including a vehicle height adjusting device that increases or decreases the vehicle height by supplying and discharging fluid, and the flow rate per unit time of the fluid discharged from the fluid chamber when the anti-roll moment increasing / decreasing device is abnormal is during normal vehicle height adjustment It is comprised so that it may be higher than the flow volume per unit time of the fluid discharged | emitted from the said fluid chamber (structure of Claim 6).

  According to the present invention, in order to effectively achieve the above-mentioned main problem, in the configuration of claim 6, the fluid chamber is configured to be an air chamber of an air spring (claim 7). Constitution).

  According to the configuration of the first aspect, the vehicle height is lowered when an abnormality that can occur only in the anti-roll moment smaller than the value to be generated occurs in the anti-roll moment increasing / decreasing device. The distance to the roll center of the vehicle can be reduced, and the roll moment acting on the vehicle can be reduced in a situation where a lateral force acts on the vehicle such as when the vehicle is turning. When the abnormality occurs in the vehicle, the increase in the roll of the vehicle and the accompanying decrease in the steering stability of the vehicle can be effectively suppressed.

  As is well known, the lateral acceleration of the vehicle can be estimated based on the vehicle speed and the steering angle, and the deviation between the estimated lateral acceleration of the vehicle based on the vehicle speed and the steering angle and the lateral acceleration of the vehicle detected by the lateral acceleration detecting means can be estimated. The size is small. However, when an abnormality occurs in the anti-roll moment increasing / decreasing device and the roll of the vehicle increases and the tilt angle of the vehicle in the left-right direction increases, the direction in which the lateral force acts on the vehicle and the direction in which the lateral acceleration detection means detects the lateral acceleration are different. Therefore, the deviation between the actual lateral acceleration magnitude of the vehicle and the lateral acceleration magnitude detected by the lateral acceleration detection means increases, and the estimated lateral acceleration magnitude of the vehicle and the vehicle detected by the lateral acceleration detection means. The deviation from the magnitude of the lateral acceleration also increases. Therefore, whether or not the anti-roll moment increasing / decreasing device is abnormal can be estimated from the magnitude of the deviation between the estimated lateral acceleration of the vehicle and the lateral acceleration detected by the lateral acceleration detecting means.

  According to the configuration of the second aspect, when the magnitude of the deviation between the estimated lateral acceleration of the vehicle based on the vehicle speed and the steering angle and the lateral acceleration of the vehicle detected by the lateral acceleration detecting means is equal to or greater than the lateral acceleration reference value. Since it is determined that the anti-roll moment increasing / decreasing device is abnormal, it can be determined when the anti-roll moment increasing / decreasing device is abnormal.

  According to the configuration of claim 3, 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 target rotational angle and the actual rotational angle of the actuator are included. When the anti-roll moment increasing / decreasing device is abnormal, it is determined that the anti-roll moment increasing / decreasing device is abnormal. it can.

  According to the fourth aspect of the present invention, the vehicle height control means includes the front wheel side vehicle height control means and the rear wheel side vehicle height control means. When an abnormality occurs in the anti-roll moment increasing / decreasing device, the vehicle height on the front wheel side is adjusted. Is reduced before the rear wheel side vehicle height, the front wheel side vehicle height can be reduced in preference to the rear wheel side vehicle height in time, thereby reducing the front wheel side vehicle height and Compared to the case where the vehicle height on the rear wheel side is lowered at the same time, or the case where the vehicle height on the rear wheel side is lowered with priority over the vehicle height on the front wheel side, the vehicle is turning. Travel stability can be improved reliably.

  In general, when the suspension spring is an air spring that can supply and discharge high-pressure air to and from the air chamber, the vehicle height can be increased or decreased by supplying and discharging high-pressure air to and from the air chamber. The smaller the smaller, the higher the spring constant of the air spring. When high-pressure air is discharged from the air chamber, the vehicle height decreases and the spring constant of the air spring increases.

  According to the configuration of the fifth aspect, at least the front wheel side vehicle height control means is an air spring capable of supplying and discharging high pressure air to and from the air chamber, so that the front wheel side vehicle height is higher than the rear wheel side vehicle height. When it is reduced with priority over time, the spring constant of the air spring on the front wheel side is increased, the roll rigidity on the front wheel side is increased, and the vehicle steering characteristic is changed to the understeer side, which also turns the vehicle It is possible to reliably improve the running stability at times.

  Further, according to the configuration of claim 6, the vehicle height control means includes a vehicle height adjusting device that increases or decreases the vehicle height by supplying / discharging fluid to / from a fluid chamber provided corresponding to each wheel, and includes an anti-roll moment increasing / decreasing device. Since the flow rate per unit time of fluid discharged from the fluid chamber is higher than the flow rate per unit time of fluid discharged from the fluid chamber during normal vehicle height adjustment, the anti-roll moment increasing / decreasing device When an abnormality occurs, the vehicle height can be quickly reduced, thereby effectively suppressing the increase in the roll of the vehicle and the accompanying decrease in the steering stability of the vehicle.

  According to the seventh aspect of the present invention, since the fluid chamber is an air chamber of an air spring, the air flow is controlled when the anti-roll moment increasing / decreasing device is abnormal by controlling the discharge flow rate of the high-pressure air from the air chamber. The flow rate per unit time of the high-pressure air discharged from the chamber can be easily and reliably made higher than the flow rate per unit time of the high-pressure air discharged from the air chamber during normal vehicle height adjustment.

[Preferred embodiment of problem solving means]
According to one preferred aspect of the present invention, in the configuration of any of claims 1 to 7, the anti-roll moment increasing / decreasing device includes an anti-roll moment applying means for applying an anti-roll moment to the vehicle, and a roll moment acting on the vehicle. Roll moment estimation means for estimating the anti-roll moment, and control means for controlling the anti-roll moment according to the estimated roll moment to increase / decrease the anti-roll moment (preferred aspect 1).

  According to another preferred aspect of the present invention, in the configuration of the preferred aspect 1, the magnitude of the roll moment estimated by the roll moment estimating means is smaller than the actual magnitude of the roll moment acting on the vehicle. When abnormality occurs, the abnormality determining means is configured to determine that the anti-roll moment increasing / decreasing device is abnormal (Preferred aspect 2).

  According to another preferred aspect of the present invention, in the configuration of claim 1 or 2 or 4 to 7, the anti-roll moment increasing / decreasing device is an actuator for rotating the two-part stabilizer and the torsion bar of the stabilizer relative to each other. (Preferred aspect 3).

  According to another preferred aspect of the present invention, in the configuration of the above first to seventh aspects, the anti-roll moment increasing / decreasing device is configured to include a suspension capable of increasing / decreasing the wheel support load (Preferable Aspect 4). ).

  According to another preferred aspect of the present invention, the anti-roll moment increasing / decreasing device includes the front wheel side anti-roll moment increasing / decreasing device and the rear wheel side anti-static device. The abnormality determination means is configured to determine that an abnormality has occurred in the anti-roll moment increasing / decreasing device when an abnormality has occurred in any of the anti-roll moment increasing / decreasing devices (Preferred aspect 5).

  According to another preferred aspect of the present invention, in the configuration of the above-described claims 1 to 7 or the preferred aspects 1 to 5, the vehicle height control means is configured to reduce the vehicle height when the anti-roll moment increasing / decreasing device is abnormal. The vehicle is configured to be lowered to the minimum vehicle height (preferred aspect 6).

  According to another preferred aspect of the present invention, in the configuration of claim 2, the abnormality determining means is based on the vehicle characteristics, vehicle speed and steering angle when the anti-roll moment increasing / decreasing device is normal. The estimated lateral acceleration is calculated (preferred aspect 7).

  According to another preferred aspect of the present invention, in the configuration of claim 2, the abnormality determining means includes means for estimating a roll moment acting on the vehicle, and the magnitude of the estimated roll moment is large. The lateral acceleration reference value is variably set according to the estimated roll moment so that the lateral acceleration reference value increases (preferred aspect 8).

  According to another preferred aspect of the present invention, in the configuration of claim 3, the anti-roll moment increasing / decreasing device includes means for estimating a roll moment acting on the vehicle, and the target rotation angle of the actuator is estimated. It is configured to be calculated based on the roll moment (preferred aspect 9).

  According to another preferred aspect of the present invention, in the configuration of claim 3, the abnormality determining means includes means for estimating a roll moment acting on the vehicle, and the magnitude of the estimated roll moment is large. The rotation angle reference value is variably set according to the estimated roll moment so that the rotation angle reference value increases (preferred aspect 10).

  According to another preferred aspect of the present invention, in the configuration of the preferred aspects 8 to 10, the means for estimating the roll moment acting on the vehicle includes means for detecting or estimating a lateral acceleration of the vehicle, and at least The roll moment acting on the vehicle is estimated based on the detected or estimated lateral acceleration of the vehicle (preferred aspect 11).

  According to another preferred aspect of the present invention, in the configuration of the preferred aspect 11, the abnormality determining means determines that the anti-roll moment increasing / decreasing device is abnormal when the gain of the lateral acceleration detecting means decreases. (Preferred embodiment 12).

  According to another preferred aspect of the present invention, in the configuration of claim 4, the vehicle height control means reduces the vehicle height on the front wheel side to the minimum vehicle height when an abnormality occurs in the anti-roll moment increasing / decreasing device. It is comprised so that the vehicle height by the side of a rear wheel may be reduced after making it (preferable aspect 13).

  According to another preferred aspect of the present invention, in the configuration of claim 6 or 7, the vehicle height control means increases or decreases the anti-roll moment by changing the degree of throttling with respect to the fluid discharged from the fluid chamber. The flow rate per unit time of fluid discharged from the fluid chamber when the apparatus is abnormal is configured to be higher than the flow rate per unit time of fluid discharged from the fluid chamber during normal vehicle height adjustment (preferably Aspect 14).

  According to another preferred aspect of the present invention, in the configuration of claims 1 to 7, the alarm device is activated when the vehicle turns in a situation where the anti-roll moment increasing / decreasing device is abnormal. Constructed (preferred embodiment 15).

  According to another preferred aspect of the present invention, in the configuration according to any one of claims 1 to 7, when the frequency of turning of the vehicle is not less than a reference value in a situation where the anti-roll moment increasing / decreasing device is abnormal. Is configured to activate an alarm device (preferred aspect 16).

  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 configuration diagram showing a first 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. .

  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 applying means for applying an anti-roll moment to the vehicle (vehicle body) and increasing / decreasing 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 air suspensions of a known structure having air springs 24FL and 24FR, respectively. It also functions as a front wheel side vehicle height adjusting device that increases or decreases the vehicle height on the front wheel side by supplying and discharging. Similarly, the suspensions 22RL and 22RR of the left and right rear wheels 10RL and 10RR are air suspensions having a known structure having air springs 24RL and 24RR, respectively. The air springs 24RL and 24RR are arranged on the front wheel side by supplying and discharging air to and from the air chamber. It also functions as a front wheel side vehicle height adjustment device that increases or decreases the vehicle height.

  The actuators 20F and 20R of the active stabilizer devices 16 and 18 are controlled by the electronic control device 26, and the supply and discharge of air to and from the air chamber is controlled by the pneumatic circuit 28 being controlled by the electronic control device 30. Although not shown in detail in FIG. 1, each of the electronic control devices 26 and 30 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. 2, the pneumatic circuit 28 is connected to the air pump 32 and the air pump 32 at one end and to the air chambers of the air springs 24FL, 24FR, 24RL, and 24RR of each wheel at the other end. It includes a conduit 34, an air dryer 36 provided in the conduit 34, and a normally closed electromagnetic on-off valve 38 provided in a branch pipe portion of each conduit 34 to each wheel. A part of the conduit 34 between the air dryer 36 and the electromagnetic opening / closing valve 38 is branched into two conduit portions 34A and 34B. The conduit portion 34A is provided with an electromagnetic switching valve 40, and the conduit portion 34B has an air dryer 36. A check valve 42 that allows only the flow of air toward the air spring is provided.

  The electromagnetic switching valve 40 switches between a throttle position where the flow of the conduit portion 34A is throttled by an orifice and a communication position which allows air to freely flow through the conduit portion 34A, and is normally set to the throttle position. . One end of an air exhaust conduit 44 is connected to the conduit 34 between the air pump 32 and the air dryer 36, and the other end of the air exhaust conduit 44 is open to the atmosphere. The air discharge conduit 44 is provided with a normally closed electromagnetic on-off valve 46.

  As shown in FIG. 2, the air springs 24FL, 24FR, 24RL, and 24RR are the chamber member 54 supported by the piston rod 52A of the shock absorber 52 or the vehicle body, and the chamber member 54 and the shock absorber. The rolling chamber 56 is provided between the cylinder 52B and the cylinder 52B. The air chamber 58 is defined by these rolling diaphragms 56.

  The air pump 32, the electromagnetic on-off valve 38, the electromagnetic switching valve 40, and the electromagnetic on-off valve 46 are controlled by the electronic control unit 30, and thereby the vehicle height is adjusted by controlling the supply and discharge of air to and from the air chamber. For example, when the vehicle height is increased, the air pump 32 is activated and the electromagnetic on-off valve 38 is opened, whereby compressed air dried by the air dryer 36 is supplied to each air chamber via the conduit 34. When the vehicle height is reduced, the electromagnetic on-off valve 38 is opened and the electromagnetic on-off valve 46 is opened, whereby the air in each air chamber is discharged to the atmosphere.

  As shown in FIG. 1, the electronic control unit 26 receives a signal indicating the vehicle lateral acceleration Gy detected by the lateral acceleration sensor 60, a signal indicating the vehicle speed V detected by the vehicle speed sensor 62, and a steering angle sensor 64. A signal indicating the detected steering angle θ and a signal indicating the actual rotation angles φF and φR of the actuators 20F and 20R detected by the rotation angle sensors 66F and 66R are input. The electronic control unit 30 receives the vehicle height Hi (i = fl, fr, rl, rr) of the corresponding part from the vehicle height sensor 68i (i = fl, fr, rl, rr) provided corresponding to each wheel. The electronic control devices 26 and 30 communicate with each other and exchange necessary signals. The lateral acceleration sensor 60, the steering angle sensor 62, and the rotation angle sensors 66F and 66R detect the lateral acceleration Gy, the steering angle θ, and the rotation angles φF and φR with positive values generated when the vehicle turns to the left.

  Although not shown in the flowchart, the electronic control unit 26 estimates the roll moment acting on the vehicle based on at least the lateral acceleration Gy of the vehicle, and cancels the roll moment when the magnitude of the roll moment is greater than or equal to a reference value. The target rotation angles φFt and φRt of the actuators 20F and 20R of the active stabilizer devices 16 and 18 are calculated so that the anti-roll moment of the actuators 16 and 18 increases, and the target rotation angles φFt and φRt corresponding to the rotation angles φF and φR of the actuators 20F and 20R, respectively. This reduces the roll of the vehicle when turning. Therefore, the active stabilizer devices 16 and 18, the electronic control device 26, the lateral acceleration sensor 60, 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 stores a map corresponding to the graphs shown in FIGS. 3 and 4 and a control routine according to the flowchart shown in FIG. 5, and generates only an anti-roll moment smaller than a value to be generated. It is determined whether or not an abnormality that cannot be performed occurs in the anti-roll moment increasing / decreasing device including the active stabilizer devices 16 and 18. When the abnormality occurs, the vehicle height of each wheel is set to the minimum vehicle height with respect to the electronic control device 30. A command signal to be reduced is output, thereby lowering the vehicle height and lowering the roll moment acting on the vehicle, thereby reducing the roll of the vehicle.

  The electronic control unit 30 calculates the target vehicle height Hti (i = fl, fr, rl, rr) of each wheel in a manner known in the art, and indicates the target vehicle height Hti from the electronic control unit 26. When the command signal is not input, the vehicle height Hi of each wheel is controlled to become the corresponding target vehicle height Hti. However, when the command signal indicating the target vehicle height Hti is input from the electronic control unit 26, each wheel is controlled. The vehicle height Hi is controlled to be the target vehicle height Hti input from the electronic control unit 26.

  Next, the vehicle height control routine at the time of abnormality in the first 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 lateral acceleration Gy of the vehicle detected by the lateral acceleration sensor 60 is read. In step 20, it is determined whether or not there is an abnormality in gain reduction in the lateral acceleration sensor 60. When a positive determination is made, the process proceeds to step 170 as it is, and when a negative determination is made, the process proceeds to step 30.

In step 30, the estimated lateral acceleration Gyh of the vehicle is calculated according to the following equation 1 based on the vehicle speed V and the steering angle θ, where H is the wheel base, Kh is the stability factor, and N is the steering gear ratio. The stability factor Kh is a value when the anti-roll moment increasing / decreasing device is normal.
Gyh = V ² · (θ / N) / {(1 + KhV ² ) H} (1)

  In step 40, based on the absolute value of the estimated lateral acceleration Gyh of the vehicle, a reference value ΔGyo used for determination in step 60 described later is calculated from a map corresponding to the graph shown in FIG.

  In step 50, based on the absolute value of the estimated lateral acceleration Gyh of the vehicle, the references Δφfo and Δφro used for discrimination in steps 70 and 80 described later are calculated from the map corresponding to the graph shown in FIG. The

  In step 60, it is determined whether or not signGy (Gyh-Gy) is greater than or equal to the reference value ΔGyo using signGy as the sign of the lateral acceleration Gy of the vehicle. If an affirmative determination is made, the process proceeds to step 170 as it is. When a negative determination is made, the routine proceeds to step 70.

  In step 70, sign φf is used as a sign of the rotation angle φf of the actuator 20F of the active stabilizer device 16 to determine whether or not sign φf (φft−φf) is equal to or larger than a reference value Δφfo, and an affirmative determination is made. Sometimes the process proceeds to step 170 as it is, and when a negative determination is made, the process proceeds to step 80.

  In step 80, sign φr is used as a sign of the rotation angle φr of the actuator 20R of the active stabilizer device 18 to determine whether or not sign φr (φrt−φr) is equal to or larger than a reference value Δφro, and an affirmative determination is made. Sometimes the routine proceeds to step 170, and when a negative determination is made, the control by the routine shown in FIG. 2 is once terminated.

  In step 170, it is determined whether or not the vehicle height Hi of all the wheels is the minimum vehicle height Hmini. If an affirmative determination is made, in step 180, the vehicle height Hi of each wheel is set to the current vehicle height Hi. After the command signal to be held at the vehicle height is output to the electronic control unit 30, the process returns to step 10, and when a negative determination is made, the process proceeds to step 190.

  In step 190, the target vehicle height Hti of each wheel is set to the corresponding minimum vehicle height Hmini, and in step 200, a command signal indicating the target vehicle height Hti of each wheel and the electromagnetic switching valve 40 of the pneumatic circuit 28. Is set to the communication position, and a control signal is output to the electronic control unit 30 so that the vehicle height Hi of each wheel becomes the minimum vehicle height Hmini with the electromagnetic switching valve 40 set to the communication position. .

  Thus, according to the first embodiment shown in the figure, it is determined in step 20 whether or not there is an abnormality in gain reduction in the lateral acceleration sensor 60. In step 60, signGy (Gyh-Gy) is a reference value. It is determined whether or not ΔGyo is greater than or equal to ΔGyo. In step 70, it is determined whether or not signφf (φft−φf) is greater than or equal to a reference value Δφfo. In step 80, signφr (φrt−φr). ) Is greater than or equal to the reference value Δφro, and if an affirmative determination is made in any step, the vehicle height Hi of each wheel becomes the minimum vehicle height Hmini in steps 170-200. Is lowered.

  Therefore, according to the first embodiment shown in the figure, an abnormality that can only generate an anti-roll moment smaller than the value to be generated occurs in the anti-roll moment increasing / decreasing device including the active stabilizer devices 16, 18 and the like. In a situation where the roll amount of the vehicle body is larger than when the anti-roll moment increasing / decreasing device is normal and the anti-roll moment increasing / decreasing device is normal, the roll moment acting on the vehicle is reliably reduced due to the decrease in vehicle height. As a result, the roll amount of the vehicle body can be reliably reduced as compared with the case where the vehicle height is not lowered, and the running stability of the vehicle when turning can be improved.

  In particular, according to the first embodiment shown in the drawing, it is determined in step 20 whether or not there is an abnormality in gain reduction in the lateral acceleration sensor 60. In step 60, signGy (Gyh-Gy) is a reference value. Since it is determined whether or not ΔGyo is greater than or equal to ΔGyo, the lateral acceleration sensor 60 for estimating the roll moment acting on the vehicle as well as when an abnormality occurs in the actuator 20F or 20R of the active stabilizer device 16 or 18. Even when there is an abnormality in the gain reduction, or when an abnormality occurs in the drive energy source such as the power source that drives the actuators 20F and 20R or in the drive energy transmission system, the roll amount of the vehicle body is reliably reduced, and when turning The running stability of the vehicle can be improved.

  FIG. 6 shows a vehicle at the time of abnormality in the embodiment 2 of the vehicle roll motion control device according to the present invention, which is 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. It is a flowchart which shows a high control routine. In FIG. 6, the same step numbers as those shown in FIG. 5 are assigned to the same steps as those shown in FIG.

  In the second embodiment, when an affirmative determination is made in any one of steps 20, 60 to 80, that is, when it is determined that the anti-roll moment increasing / decreasing device is abnormal, in step 130 the previous time. It is determined whether or not the anti-roll moment increasing / decreasing device has been determined to be abnormal. If an affirmative determination is made, the process proceeds to step 150. If a negative determination is made, the process proceeds to step 140.

  In step 140, it is determined whether or not the vehicle heights Hfl and Hfr of the left and right front wheels are the minimum vehicle height Hminf of the front wheels. If an affirmative determination is made, the process proceeds to step 170 and a negative determination is made. Sometimes go to step 150.

  In step 150, the target vehicle heights Htfl and Htfr of the left and right front wheels are set to the minimum vehicle height Hminf of the front wheels, and in step 160, the target vehicle heights Htfl and Htfr of the left and right front wheels are the minimum vehicle height Hminf of the front wheels. A command signal indicating this and a command signal for setting the electromagnetic switching valve 40 of the pneumatic circuit 28 to the communication position are output to the electronic control unit 30.

  In step 170, it is determined whether or not the vehicle heights Hfl and Hfr of the left and right front wheels are the minimum vehicle height Hminf of the front wheels and whether the vehicle heights Hrl and Hrr of the left and right rear wheels are the minimum vehicle height Hminr of the rear wheels. If an affirmative determination is made, a command signal for maintaining the vehicle heights of all the wheels at the current vehicle height is output to the electronic control unit 30 at step 180. If a negative determination is made, the process goes to step 190. move on.

  In step 190, the target vehicle height Hti of all the wheels is set to the minimum vehicle height Hmini, and in step 200, a command signal indicating that the target vehicle height Hti of all the wheels is the minimum vehicle height Hmini, and A command signal for setting the electromagnetic switching valve 40 of the pneumatic circuit 28 to the communication position is output to the electronic control unit 30.

  Thus, according to the illustrated second embodiment, when an abnormality occurs in the anti-roll moment increasing / decreasing device, an affirmative determination is made in step 130, and in steps 150 and 160, the vehicle heights Hfl and Hfr of the left and right front wheels are first determined as front wheels. Lowering of the vehicle heights Hfl and Hfr of the left and right front wheels is started so as to become the minimum vehicle height Hminf, and then a negative determination is made in step 130, and the vehicle heights Hfl and Hfr of the left and right front wheels become the minimum vehicle height Hminf of the front wheels. In step 140, an affirmative determination is made. In steps 170, 190 and 200, the left and right rear wheel heights Hrl and Hrr are set such that the left and right rear wheel heights Hrl and Hrr become the minimum rear wheel height Hminr. As long as the anti-roll moment increasing / decreasing device is abnormal, the vehicle heights of all the wheels are kept at the minimum vehicle height in step 180.

  Therefore, according to the second embodiment shown in the figure, when an abnormality occurs in the anti-roll moment increasing / decreasing device, the front wheel height is lowered before the rear wheel height, so that the front wheel height is reduced to the rear wheel height. The vehicle can be leaned forward by lowering the front wheel height below the rear wheel height until the rear wheel height reaches the minimum height. Thus, when the vehicle height on the front wheel side and the vehicle height on the rear wheel side are simultaneously reduced as in the case of the above-described first embodiment, the vehicle height on the rear wheel side takes precedence over the vehicle height on the front wheel side in terms of time. As compared with the case where the vehicle is lowered, the running stability at the time of turning of the vehicle can be improved with certainty.

  In general, the spring constant of the air spring of the air suspension increases as the pressure in the air chamber increases and the volume of the air chamber decreases. Therefore, if the vehicle height is reduced by discharging high-pressure air from the air chamber, The spring constant of the spring increases.

  According to the illustrated embodiment 2, since the front wheel height is lowered before the rear wheel height, the spring constant of the air spring of the front wheel is higher than the spring constant of the air spring of the rear wheel. This increases the roll rigidity of the front wheels relative to the rear wheels and changes the steering characteristics of the vehicle to the understeer side, which also improves the running stability when the vehicle is turning. Can be made.

  In particular, according to the second embodiment shown in the drawing, the vehicle height of the rear wheels starts decreasing after the vehicle height of the front wheels reaches the minimum vehicle height. It is possible to reliably improve the running stability of the vehicle until the vehicle height of all the wheels reaches the minimum vehicle height as compared with the case where the vehicle is started.

  In Example 2 shown in the figure, the rear wheel height starts to decrease after the front vehicle height reaches the minimum vehicle height. As long as the time is given priority over the height reduction, the rear wheel height reduction may start before the front wheel height reaches the minimum height, for example, when the front wheel height reduction starts. Lowering of the rear wheel height may be started after a predetermined time.

  FIG. 7 is a flow chart showing a main part of an alarm control routine for an occupant at the time of abnormality in the third embodiment of the vehicle roll motion control apparatus according to the present invention, which is configured as a modification of the first or second embodiment.

  In the third embodiment, when an affirmative determination is made in any of steps 20 and 60 to 80 of the first or second embodiment, it is determined that the active stabilizer device 16 or 18 is abnormal. Then, in step 90, it is determined whether or not the absolute value of the estimated lateral acceleration Gyh of the vehicle is greater than or equal to a reference value Gyho (positive constant). If an affirmative determination is made, the process proceeds directly to step 120. When a negative determination is made, the routine proceeds to step 100.

  In step 100, whether the frequency at which the absolute value of the lateral acceleration Gy of the vehicle exceeds the reference value Gyo (positive constant) during a predetermined time To (positive constant) is e (positive constant)% or more. It is determined whether or not the vehicle is in a driving situation in which turning with a relatively large magnitude of the lateral acceleration Gy is performed. If a negative determination is made, step 110 is executed in step 110. After the alarm lamp not shown in FIG. 6 is turned off, the process proceeds to step 170 (in the case of the modification of the first embodiment) or step 130 (in the case of the modification of the second embodiment). Then, after the warning lamp is turned on, the process proceeds to step 170 (in the case of the modification of the first embodiment) or step 130 (in the case of the modification of the second embodiment).

  Thus, according to the illustrated third embodiment, the effects of the first or second embodiment described above can be obtained, and the vehicle turns while the anti-roll moment increasing / decreasing device is abnormal, and the estimated lateral acceleration Gyh of the vehicle is reduced. If the absolute value is greater than or equal to the reference value Gyho, or if the anti-roll moment increasing / decreasing device is abnormal and the vehicle turns more frequently than the reference value, an alarm lamp as an alarm device is lit. A warning indicating that the roll moment increasing / decreasing device is abnormal can be issued, and the driver can be alerted not to perform an operation in which an excessive roll moment acts on the vehicle.

  In particular, according to the illustrated embodiment 3, the alarm lamp is lit only when the driver needs to be alerted. For example, when the anti-roll moment increasing / decreasing device is abnormal, the alarm lamp is always lit. Compared to the above, it is possible to reduce a possibility that the vehicle occupant feels bothersome.

  According to the above-described embodiments, the pneumatic circuit 28 that controls the supply and discharge of high-pressure air to the air springs 24FL to 24RR has the electromagnetic switching valve 40, and the electromagnetic switching valve 40 restricts the flow of the conduit portion 34A by the orifice. When the vehicle height Hi of each wheel is lowered to the minimum vehicle height Hmini, the throttle position and the communication position allowing air to freely flow in the conduit portion 34A are switched. The switching valve 40 is set to the communication position. Accordingly, even when the vehicle height Hi of each wheel is lowered to the minimum vehicle height Hmini, the vehicle height Hi of each wheel is quickly reduced to the minimum vehicle height Hmini as compared with the case where high-pressure air must pass through the orifice. Thus, the vehicle height can be quickly reduced immediately after an abnormality occurs in the anti-roll moment increasing / decreasing device.

  Further, according to each of the embodiments described above, the estimated lateral acceleration is such that the reference value ΔGyo used for determining the deviation of the lateral acceleration deviation of the vehicle in step 60 increases as the absolute value of the estimated lateral acceleration Gyh of the vehicle increases. Since it is variably set according to the absolute value of Gyh, for example, whether the anti-roll moment increasing / decreasing device is abnormal regardless of the magnitude of the roll moment acting on the vehicle as compared with the case where the reference value ΔGyo is a constant value Whether or not can be accurately determined.

  Similarly, according to the above-described embodiments, the reference values Δφfo and Δφro used for determining the magnitude of the deviation of the rotation angle of the actuators 20F and 20R in steps 70 and 80 are also absolute values of the estimated lateral acceleration Gyh of the vehicle. Since it is variably set according to the absolute value of the estimated lateral acceleration Gyh so as to increase, the roll moment acting on the vehicle is related to the magnitude of the roll moment acting on the vehicle compared to the case where the reference values Δφfo and Δφro are constant values, for example. It is possible to accurately determine whether or not the anti-roll moment increasing / decreasing device is abnormal.

  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 embodiments, the reference values ΔGyo, Δφfo, Δφro are variably set according to the absolute value of the estimated lateral acceleration Gyh, but these reference values are constant values. Alternatively, it may be modified so as to be variably set in accordance with the detected lateral acceleration Gy of the vehicle.

  In each of the above-described embodiments, the anti-roll moment is increased by the active stabilizer device to reduce the roll of the vehicle. The means for increasing the anti-roll moment is, for example, a wheel suspension such as an active suspension. Any means known in the art that can increase or decrease the ground load may be used.

  In each of the above-described embodiments, the suspension is an air suspension, and the vehicle height is increased or decreased by supplying or discharging high-pressure air to or from the air chamber. The apparatus may be applied to a vehicle having a suspension other than an air suspension, and the vehicle height adjusting means may be any means known in the art such as a hydropneumatic suspension as long as the vehicle height can be adjusted. It's okay.

  In each of the above-described embodiments, the roll moment acting on the vehicle is estimated based on at least the lateral acceleration Gy of the vehicle, and when the magnitude of the roll moment is greater than or equal to a reference value, the anti-roll in a direction that cancels the roll moment. The active stabilizer devices 16 and 18 are controlled so as to increase the moment, but the roll moment may be estimated based on the lateral acceleration Gy and other vehicle information, and vehicle information other than the lateral acceleration Gy may be included. May be estimated.

  Further, according to each of the embodiments described above, the pneumatic circuit 28 that controls the supply and discharge of high-pressure air to the air springs 24FL to 24RR has the electromagnetic switching valve 40, and the electromagnetic switching valve 40 restricts the flow of the conduit portion 34A by the orifice. When the vehicle height Hi of each wheel is lowered to the minimum vehicle height Hmini, the throttle valve 40 is configured to switch to the throttle position and the communication position that allows air to freely flow in the conduit portion 34A. Although the communication position is set, the electromagnetic switching valve 40 and the switching thereof may be omitted.

  Further, when the anti-roll moment increasing / decreasing device includes an active stabilizer device, the abnormality of the anti-roll moment increasing / decreasing device detects the torque of the torsion bar portion, and the detected torque and the control command value for the actuator of the active stabilizer device are detected. It may be determined based on the relationship.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram showing a first embodiment of a vehicle roll motion control device according to the present invention applied to a vehicle in which an active stabilizer device is provided on the front wheel side and the rear wheel side and the suspension of each wheel is an air suspension. It is explanatory drawing which shows the pneumatic circuit shown by FIG. It is a graph which shows the relationship between the absolute value of the estimated lateral acceleration Gyh of a vehicle, and the reference value (DELTA) Gyo of lateral acceleration deviation. It is a graph which shows the relationship between the absolute value of the estimated lateral acceleration Gyh of a vehicle, and reference value (DELTA) phifo, (DELTA) phiro of rotation angle deviation. 3 is a flowchart showing a vehicle height control routine at the time of abnormality in the first embodiment. Vehicle height control control at the time of abnormality in the embodiment 2 of the 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. It is a flowchart which shows a routine. It is a flowchart which shows the principal part of the warning control routine with respect to the passenger | crew at the time of abnormality in Example 3 of the rolling motion control apparatus of the vehicle by this invention comprised as a modification of the above-mentioned Example 1 or 2.

Explanation of symbols

16, 18 Active stabilizer device 20F, 20R Actuator 24FL-24RR Air spring 26, 30 Electronic control device 28 Pneumatic circuit 40 Electromagnetic switching valve 60 Lateral acceleration sensor 62 Vehicle speed sensor 64 Steering angle sensor 66F, 66R Rotation angle sensor 68i Vehicle height sensor

Claims (7)

  A roll motion control device for a vehicle having an anti-roll moment increasing / decreasing device that increases the anti-roll moment to reduce the roll of the vehicle when the roll moment acts on the vehicle, and generates only an anti-roll moment smaller than the value to be generated. An abnormality determining means for determining that an abnormality that cannot be performed has occurred in the anti-roll moment increasing / decreasing device, and a vehicle height control means for reducing the vehicle height when the anti-roll moment increasing / decreasing device is abnormal. A rolling motion control device for a vehicle.   The abnormality determination means increases or decreases the anti-roll moment when the magnitude of the deviation between the estimated lateral acceleration of the vehicle based on the vehicle speed and the steering angle and the lateral acceleration of the vehicle detected by the lateral acceleration detection means is equal to or greater than a lateral acceleration reference value. The vehicle roll motion control device according to claim 1, wherein the device is determined to be abnormal.   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 magnitude of deviation between the target rotation angle of the actuator and the actual rotation angle is the rotation angle. 2. The vehicle roll motion control device according to claim 1, wherein the anti-roll moment increasing / decreasing device determines that the anti-roll moment increasing / decreasing device is abnormal when it is equal to or greater than a reference value.   The vehicle height control means comprises a front wheel side vehicle height control means and a rear wheel side vehicle height control means, and when an abnormality occurs in the anti-roll moment increasing / decreasing device, the vehicle height on the front wheel side is made higher than the vehicle height on the rear wheel side. 4. The vehicle roll motion control device according to claim 1, wherein the roll motion control device is lowered first.   5. The roll motion control device for a vehicle according to claim 4, wherein at least the front wheel side vehicle height control means is an air spring capable of supplying and discharging high pressure air to and from an air chamber.   The vehicle height control means includes a vehicle height adjusting device that increases / decreases the vehicle height by supplying / discharging fluid to / from a fluid chamber provided corresponding to each wheel, and the fluid chamber when the anti-roll moment increasing / decreasing device is abnormal. 6. The vehicle according to claim 1, wherein a flow rate per unit time of the fluid discharged is higher than a flow rate per unit time of the fluid discharged from the fluid chamber during normal vehicle height adjustment. Roll motion control device. The vehicle roll motion control device according to claim 6, wherein the fluid chamber is an air chamber of an air spring.

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