JP2012166736A - Air suspension control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air suspension control device for a vehicle, which can securely perform crouching control and of which the consumption of compressed air can be suppressed, while preventing either right or left front wheel of the vehicle from lifting even when height of road surfaces with which front wheels of the vehicle come in contact are different between the right and left front wheels.SOLUTION: In a normal mode of step S1 in which crouching control and vehicle height adjustment control are not performed, it is determined whether, the vehicle is on an undulated road in step S2, and when the vehicle is on the undulated road, respective leveling control in the vehicle rear right and left is compulsorily stopped in step S3.

Description

  The present invention relates to a vehicle air suspension control device.

  In general, in the case of a vehicle such as a bus equipped with an air suspension control device and having an entrance at the front side, the wheel moves up and down due to unevenness or inclination of the road surface or the vehicle body tilts when stopping or running Even if it is going to do, leveling control to hold the car body parallel to the axle by holding the left and right vehicle heights independently at a constant height is performed, but when passengers get on and off, the entrance / exit is Crouching control is performed to lower the vehicle height at the front part of the vehicle so that passengers can easily get on and off.

  FIG. 2 is an overall schematic configuration diagram showing an example of a conventional vehicle air suspension control device, in which 1 is a vehicle such as a bus, 2 is a front wheel of the vehicle 1, and 3 is a rear wheel of the vehicle 1. The air suspension control device is provided with a total of four front air springs 4 arranged one by one on the left and right so as to support the front wheel 2 and two pieces on the left and right two sides so as to support the rear wheel 3. A rear air spring 5, a front vehicle height adjustment valve 8 provided in an air pipe 7 connecting the front air spring 4 and the air tank 6, and supplying / discharging compressed air in the air tank 6 to / from the front air spring 4, respectively; Provided in an air line 9 that branches off from the air line 7 and connects the rear air spring 5 and the air tank 6 to the rear air spring 5. A rear vehicle height adjustment valve 10 for supplying and discharging the vehicle, a front vehicle height sensor 11 such as a potentiometer for electrically detecting left and right vehicle heights 11a at the front portion of the vehicle 1, and a left and right vehicle heights 12a at the rear portion of the vehicle 1 respectively. A rear vehicle height sensor 12 such as a potentiometer that is electrically detected, and a front vehicle height adjustment valve 8 and a rear vehicle height based on vehicle heights 11a and 12a detected by the front vehicle height sensor 11 and the rear vehicle height sensor 12. And a controller 13 that outputs control signals 8a and 10a to the regulating valve 10.

  In addition, the driver's seat of the vehicle 1 such as the bus is configured to perform crouching control so that the front portion of the vehicle 1 is lowered when the driver is turned ON / OFF and a predetermined condition is satisfied in the ON state. A crouching switch 14 is provided, and the crouching switch 14 is connected to the controller 13.

  Although not shown, the controller 13 is also connected to a vehicle height adjustment control switch for performing vehicle height adjustment control for raising and lowering the vehicle height of the vehicle 1 to a required height as necessary. It is used when parking at low parking lots or when boarding a ferry.

  In the vehicle air suspension control device, when the vehicle is stopped or running, the front vehicle height sensor 11 detects the left and right vehicle heights 11a at the front of the vehicle 1 and inputs them to the controller 13. In the controller 13, the vehicle 13 An average value of the left and right vehicle heights 11a in one front is calculated, and the average value is compared with a preset reference range, and the left and right vehicle heights 11a in the front of the vehicle 1 are compared with the reference range. When the average value is low, compressed air is simultaneously supplied to the left and right front air springs 4 by the control signal 8a to the front vehicle height adjusting valve 8, and the average value of the left and right vehicle heights 11a at the front portion of the vehicle 1 from the reference range is When it is high, compressed air is discharged simultaneously from the left and right front air springs 4 by a control signal 8a to the front vehicle height adjustment valve 8. It is. At the same time, the rear vehicle height sensor 12 detects the left and right vehicle heights 12a at the rear of the vehicle 1 and inputs them to the controller 13. In the controller 13, the left and right vehicle heights 12a at the rear of the vehicle 1 are set in advance as a reference. When the left and right vehicle heights 11a at the rear portion of the vehicle 1 are lower than the reference range, compressed air is supplied to the left and right rear air springs 5 by the control signal 10a to the rear vehicle height adjusting valve 10. On the contrary, when the left and right vehicle heights 11a at the rear portion of the vehicle 1 are higher than the reference range, the compressed air is discharged from the left and right rear air springs 5 by the control signal 10a to the rear vehicle height adjusting valve 10. In this way, leveling control is performed, and the left and right vehicle heights are independently maintained at a constant height even if the wheels move up and down due to the unevenness or inclination of the road surface or the vehicle body tilts. The vehicle body is held parallel to the axle. It is well known that the inclination correction of the vehicle 1 is more effective when it is performed on the rear axle side with a large axial load and a wide tread.

  On the other hand, when the driver runs the vehicle 1, arrives at a stop or the like, stops the vehicle 1, and operates the parking brake, when the crouching switch 14 is turned on by the driver, as described above, The front vehicle height sensor 11 detects the left and right vehicle heights 11a at the front portion of the vehicle 1 and inputs them to the controller 13. The controller 13 calculates the average value of the left and right vehicle heights 11a at the front portion of the vehicle 1, The average value is compared with a reference range for crouching control set in advance lower than the reference range, and the average value of the left and right vehicle heights 11a at the front portion of the vehicle 1 is within the reference range for crouching control. Simultaneously from the left and right front air springs 4 by a control signal 8a output from the controller 13 to the front vehicle height adjustment valve 8. Condensed air is discharged. In this way, in the case of a vehicle 1 such as a bus provided with a boarding gate at the front side, crouching control is performed, and the vehicle height at the front of the vehicle 1 provided with the boarding gate is lowered when passengers get on and off. It becomes possible to easily get on and off passengers.

  For example, Patent Document 1 shows a general technical level related to the vehicle air suspension control apparatus as described above.

Japanese Patent Laid-Open No. 7-205630

  However, for example, on an uphill road, as shown in FIG. 3, the height of the road surface on which the front wheel 2 on the right side of the vehicle 1 contacts is significantly higher than the left side, and the rear wheel 3 of the vehicle 1 (see FIG. 3). The road surface to be grounded is a “swell road” where the right side is lower than the front wheel 2 side, and crouching control is performed as described above. When the compressed air is discharged from the left and right front air springs 4 at the front of the vehicle 1 at the same time, the bump stopper built in the right front air spring 4 comes into contact with the upper plate of the front air spring 4. As a result, the rubber contact state that cannot be further contracted in the height direction is sometimes caused.

  If the right front air spring 4 is in a rubber contact state before the average value of the left and right vehicle heights 11a in the front portion of the vehicle 1 falls within the reference range for crouching control, the left front air spring 4 Further, the compressed air is continuously discharged. However, if the average value of the left and right vehicle heights 11a at the front portion of the vehicle 1 does not fall to the reference range for crouching control, the inside of the front air spring 4 on the left side is left. There is almost no compressed air, and the left front air spring 4 is further compressed by a stabilizer reaction force.

  Moreover, at the same time, compressed air is supplied to the left rear air spring 5 at the rear portion of the vehicle 1, and compressed air is discharged from the right rear air spring 5 at the rear portion of the vehicle 1, Since the leveling control works so that the vehicle body is parallel to the right-downward road surface on which the rear wheel 3 of the vehicle 1 is in contact with the ground, the front wheel 2 on the left side of the vehicle 1 is lifted up and becomes very unstable. There was a bug.

  For example, as shown in FIG. 3, the height of the road surface on which the front wheel 2 on the right side of the vehicle 1 contacts is significantly higher than that on the left side, and the height of the road surface on which the rear wheel 3 of the vehicle 1 contacts is Even in a situation where there is almost no difference in height between the left and right front wheels 2 on the right and left, the crouching control is performed and compressed air is discharged simultaneously from the left and right front air springs 4 at the front of the vehicle 1. In this case, as described above, the bump stopper built in the right front air spring 4 comes into contact with the upper surface plate of the front air spring 4 and cannot be further contracted in the height direction, so that it is in a rubber contact state. You may fall into it. If the right front air spring 4 is in a rubber contact state before the average value of the left and right vehicle heights 11a in the front portion of the vehicle 1 falls within the reference range for crouching control, the left front air spring 4 Further, since the compressed air is continuously discharged, not only the vehicle height 11a on the left side in the front portion of the vehicle 1 but also the vehicle height 12a on the left side in the rear portion of the vehicle 1 is lowered. When the vehicle is tilted to the left, the leveling control still works, and the compressed air is supplied to the left rear air spring 5 at the rear of the vehicle 1, so that the front wheel 2 on the left side of the vehicle 1 does not lift up as described above. The average value of the left and right vehicle heights 11a at the front portion of the vehicle 1 is increased, and the average value of the left and right vehicle heights 11a should be within the reference range for crouching control. Compressed air is discharged from the front air spring 4 on the left side and the left side, and thereafter, the same operation as described above is repeated, the crouching control and the leveling control are alternately performed, the control is not converged, and all the compressed air in the air tank 6 is exhausted. There was a possibility that the vehicle body would continue to move up and down until it was consumed.

  In view of such circumstances, the present invention reliably performs the crouching control while preventing the left and right front wheels from rising even if the height of the road surface on which the front wheels of the vehicle touch the ground is different on the left and right. It is an object of the present invention to provide a vehicle air suspension control device that can control the consumption of compressed air.

The present invention includes a front air spring disposed to support a front wheel of a vehicle,
A rear air spring disposed to support the rear wheel of the vehicle;
A front vehicle height adjustment valve for supplying and discharging compressed air in an air tank to the front air spring;
A rear vehicle height adjustment valve for supplying and discharging compressed air in an air tank to the rear air spring;
A front vehicle height sensor for detecting left and right vehicle heights at the front of the vehicle;
A rear vehicle height sensor for detecting left and right vehicle heights at the rear of the vehicle;
By outputting control signals to the front vehicle height adjustment valve and the rear vehicle height adjustment valve based on the vehicle heights detected by the front vehicle height sensor and the rear vehicle height sensor, the vehicle heights at the left and right at the rear of the vehicle are set to a constant height In addition, leveling control is performed to keep the vehicle body parallel to the axle, and when passengers get on and off, crouching control is performed to lower the vehicle height at the front of the vehicle where the entrance is provided. A vehicle air suspension control device comprising a controller for performing vehicle height adjustment control for raising and lowering the vehicle to a required height,
During a normal mode in which the crouching control and the vehicle height adjustment control are not performed, the absolute value of the difference between the left and right vehicle heights detected by the front vehicle height sensor is greater than or equal to a preset first threshold value And the product of the difference between the left and right vehicle heights detected by the front vehicle height sensor and the difference between the left and right vehicle heights detected by the rear vehicle height sensor is negative. Or when the absolute value of the difference between the left and right vehicle heights at the rear part of the vehicle detected by the rear vehicle height sensor and the reference vehicle height is equal to or less than a preset second threshold value, the vehicle is on a wavy road The present invention relates to a vehicle air suspension control device characterized in that it is configured to forcibly stop the left and right leveling controls at the rear of the vehicle.

  According to the above means, the following operation can be obtained.

  When configured as described above, for example, the height of the road surface on which the front wheels on the left and right sides of the vehicle are in contact with the ground is significantly higher than the left and right sides, that is, the left and right vehicles at the front of the vehicle detected by the front vehicle height sensor. The absolute value of the height difference is equal to or greater than a preset first threshold, and the height of the road surface on which the rear wheel of the vehicle touches is lower on the left and right sides as opposed to the front wheel side, that is, When the product of the difference between the left and right vehicle heights detected at the front vehicle height sensor and the difference between the left and right vehicle heights detected at the rear vehicle height sensor is negative. It is determined that the vehicle is on a wavy road, and the left and right leveling controls at the rear of the vehicle are forcibly stopped.

  When crouching control is performed from this state and compressed air is discharged simultaneously from the left and right front air springs at the front of the vehicle, the bump stopper built in the front air spring on one of the left and right sides The rubber plate is in contact with the top plate of the vehicle and cannot be further contracted in the height direction, and the compressed air is continuously discharged from the front air springs on the other side of the left and right sides. If the average value of the vehicle height does not fall to the reference range for crouching control, there is almost no compressed air in the front air spring on the other side of the left and right sides, and the front air spring on the other side of the left and right side further shrinks due to the stabilizer reaction force. However, the left and right leveling controls at the rear of the vehicle are already suspended. Therefore, the left and right rear air springs at the rear of the vehicle are not supplied and discharged with compressed air, and leveling control is performed so that the vehicle body is parallel to the right-downward road surface on which the rear wheel of the vehicle contacts the ground. There is no worry that the front wheels on the left and right sides of the vehicle will float up and become very unstable.

  Further, for example, the height of the road surface on which the front wheels on the left and right sides of the vehicle are in contact with the ground is significantly higher than the other side, that is, the difference between the left and right vehicle heights detected at the front vehicle height sensor. The absolute value is equal to or greater than a preset first threshold value, and the height of the road surface on which the rear wheel of the vehicle touches has little difference between the left and right sides, that is, the rear portion of the vehicle detected by the rear vehicle height sensor. If the absolute value of the difference between the left and right vehicle heights in the vehicle and the reference vehicle height is less than or equal to a preset second threshold, it is determined that the vehicle is on a wavy road, and the left and right leveling at the rear of the vehicle Since the control is forcibly stopped, if crouching control is performed from this state and compressed air is discharged simultaneously from the left and right front air springs at the front of the vehicle, the front air springs on the left and right sides will be The stored bump stopper contacts the top plate of the front air spring and falls into a rubber contact state where it can no longer shrink in the height direction, and compressed air continues from the front air spring on the other side. As a result of this operation, not only the vehicle height on the other left and right sides in the front part of the vehicle but also the vehicle height on the other left and right side in the rear part of the vehicle is lowered and the vehicle is tilted to the other side. Compressed air is not supplied to the rear air springs on the other side of the left and right sides in the rear part, and it is avoided that the average value of the left and right vehicle heights in the front part of the vehicle becomes high. It will be done reliably.

  As a result, it is avoided that crouching control and leveling control are alternately performed so that control does not converge, and the vertical movement of the vehicle body continues until all the compressed air in the air tank is consumed. No longer occurs.

  According to the vehicle air suspension control device of the present invention, the crouching control is performed while preventing the front wheels on the left and right sides of the vehicle from being lifted even if the height of the road surface on which the front wheels of the vehicle touch the ground is different on the left and right. An excellent effect can be obtained that can be reliably performed and consumption of compressed air can be suppressed.

It is a flowchart which shows the Example of the air suspension control apparatus for vehicles of this invention. It is a whole schematic block diagram which shows an example of the conventional air suspension control apparatus for vehicles. It is the schematic which shows the state where the road surface in the right side of a vehicle is high as an example of the situation where the height of the road surface which the front wheel of a vehicle contacts differs significantly on right and left.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a first embodiment of a vehicle air suspension control apparatus according to the present invention, and the basic configuration is the same as the conventional one shown in FIGS. As shown in FIG. 1, during normal mode, it is determined whether or not the vehicle 1 is on a wavy road. If the vehicle 1 is on a wavy road, the left and right leveling control at the rear of the vehicle 1 is forcibly performed. The point is that it is configured to be paused.

  First, in step S1 of FIG. 1, the normal mode refers to a state in which no crouching control or vehicle height adjustment control is performed during traveling or stopping.

  In step S2 in FIG. 1, it is determined whether or not the vehicle 1 is on a wavy road. For example, as shown in FIG. 3, the height of the road surface on which the front wheel 2 on the right side of the vehicle 1 contacts is significantly higher than that on the left side. The height of the road surface on which the rear wheel 3 (not shown in FIG. 3) of the vehicle 1 contacts is lower on the right side as opposed to the front wheel 2 side, or, for example, As shown in FIG. 3, the height of the road surface on which the front wheel 2 on the right side of the vehicle 1 contacts is remarkably higher than that on the left side, and the height of the road surface on which the rear wheel 3 of the vehicle 1 contacts is on the left side of the vehicle 1. It is possible to determine that the vehicle 1 is on a wavy road in any situation where there is almost no difference in height on the left and right sides, which is equal to the height of the road surface on which the front wheels 2 are in contact with the ground.

Here, the determination of the swell road in the step S2 is expressed by a mathematical expression:
[Equation 1]
| FR-FL | ≧ ΔF0
Where FR: right vehicle height at the front of the vehicle 1 FL: left vehicle height at the front of the vehicle 1 ΔF0: absolute value threshold (first threshold) of left and right vehicle height differences at the front of the vehicle 1
And [Equation 2]
(FR-FL) × (RR-RL) ≦ 0
RR: right vehicle height at the rear of the vehicle 1 RL: left vehicle height at the rear of the vehicle 1 or [Equation 3]
(| RR-RS | ≦ ΔR0 and | RL-RS | ≦ ΔR0)
However, RS: reference vehicle height at the rear of the vehicle 1 ΔR0: threshold of absolute value of difference between the left and right vehicle heights at the rear of the vehicle 1 and the reference vehicle height (second threshold)
It becomes.

  That is, the condition of [Equation 1] is that the absolute value of the difference between the left and right vehicle heights 11a detected by the front vehicle height sensor 11 (see FIG. 2) is equal to or greater than a preset first threshold value ΔF0. The condition of [Expression 2] indicates that the difference between the left and right vehicle heights 11a detected by the front vehicle height sensor 11 and the vehicle detected by the rear vehicle height sensor 12 (see FIG. 2). 1 shows a case where the product of the difference between the left and right vehicle heights 12a at the rear is negative, and the condition of [Equation 3] is that the left and right vehicle heights 12a at the rear of the vehicle 1 detected by the rear vehicle height sensor 12 and the reference The case where the absolute value of the difference from the vehicle height is less than or equal to a preset second threshold value ΔR0 is shown, and the condition of [Expression 1] and [Expression 2], or [Expression 1] and [Expression 3] If the condition is satisfied, it is determined that the vehicle 1 is on a wavy road, and the process goes to step S3. Thus, the left and right leveling controls at the rear of the vehicle 1 are forcibly stopped.

  Incidentally, the first threshold value ΔF0 can be set to 78 [mm], for example, but is not limited to this value, and may be appropriately selected from the range of 20 to 150 [mm].

  The second threshold value ΔR0 can be set to 5 [mm], for example, but is not limited to this value, and may be appropriately selected from a range of 0 to 40 [mm].

  It should be noted that the road surface where the front wheel 2 of the vehicle 1 touches the road surface has almost no difference in height, and the road surface where the rear wheel 3 of the vehicle 1 touches the road surface has a significant difference in height. However, it can be said that the road is a wavy road, but if such conditions are added to the determination of the wavy road, control interference may occur. Comparison with the threshold value is not performed.

  If it is determined in step S2 that the vehicle 1 is not on a wavy road, the left and right leveling controls at the rear of the vehicle 1 are not forcibly stopped and the process proceeds to step S4 described later. .

  Subsequently, in step S4, it is detected whether or not the crouching switch 14 has been turned on by the driver. If the crouching switch 14 has not been turned on by the driver, the process returns to step S2 and the vehicle 1 On the other hand, when the crouching switch 14 is turned on by the driver, the average value of the left and right vehicle heights 11a at the front portion of the vehicle 1 is determined in step S5. It is determined whether or not it is within the reference range for crouching control, and if the average value of the left and right vehicle heights 11a at the front portion of the vehicle 1 is not within the reference range for crouching control, the front portion of the vehicle 1 is determined in step S6. Whether the average value of the left and right vehicle heights 11a is higher than the reference range for crouching control, If the average value of the left and right vehicle heights 11a at the front part is higher than the reference range for crouching control, compressed air is discharged from the left and right front air springs 4 at step S7 to lower the vehicle height 11a at the front part of the vehicle 1. To.

  Conversely, if the average value of the left and right vehicle heights 11a at the front of the vehicle 1 is lower than the reference range for crouching control, compressed air is supplied to the left and right front air springs 4 at step S8, and the vehicle at the front of the vehicle 1 is Increase the height 11a.

  After the operation of either step S7 or step S8 is performed, the process returns to step S5 to check again whether or not the average value of the left and right vehicle heights 11a in the front portion of the vehicle 1 is within the reference range for crouching control. If the average value of the left and right vehicle heights 11a at the front part of the vehicle 1 is within the reference range for crouching control, the vehicle height 11a at the front part of the vehicle 1 is held at that position, and passengers get on and off. To make it easier.

  Thereafter, it is detected in step S9 whether or not the crouching switch 14 has been turned OFF by the driver. If the crouching switch 14 has been turned OFF by the driver, the crouching control is ended in step S10, and the vehicle The vehicle height 11a at the front part is returned to the original position, and the left and right leveling controls at the rear part of the vehicle 1 are resumed at step S11, and the process returns to step 1.

  When configured as described above, for example, on an uphill road, as shown in FIG. 3, the height of the road surface on which the front wheel 2 on the right side of the vehicle 1 contacts is significantly higher than that on the left side, that is, with the front vehicle height sensor 11. The absolute value of the difference between the left and right vehicle heights 11a detected at the front of the vehicle 1 is equal to or greater than a preset first threshold value ΔF0 (see [Equation 1]), and the rear wheel 3 of the vehicle 1 (see FIG. 3). The height of the road surface to be grounded is lower on the right side as opposed to the front wheel 2 side, that is, the left and right vehicle heights 11 a at the front of the vehicle 1 detected by the front vehicle height sensor 11. And the difference between the left and right vehicle heights 12a detected at the rear of the vehicle 1 detected by the rear vehicle height sensor 12 is negative (see [Equation 2]), the vehicle 1 is in a wavy road. Left and right leveling at the rear of the vehicle 1 Control is forcibly pause.

  When crouching control is performed from this state and compressed air is discharged simultaneously from the left and right front air springs 4 at the front of the vehicle 1, the bump stopper built in the right front air spring 4 is used for the front air spring 4. 4 is brought into a rubber contact state where it cannot be further contracted in the height direction by contact with the upper surface plate 4, and the compressed air is continuously discharged from the left front air spring 4. If the average value of the vehicle height 11a does not fall to the reference range for crouching control, there is almost no compressed air in the left front air spring 4 and the left front air spring 4 is further contracted by the stabilizer reaction force. The left and right leveling controls at the rear of the vehicle 1 are already suspended. Therefore, the left and right rear air springs 5 at the rear of the vehicle 1 are leveled so that compressed air is not supplied and discharged and the vehicle body is parallel to the right-downward road surface on which the rear wheel 3 of the vehicle 1 contacts the ground. It is avoided that the control works, and there is no worry that the front wheel 2 on the left side of the vehicle 1 is lifted up and becomes very unstable.

  Note that the crouching control is performed even if a change in the posture of the vehicle 1 occurs while the passenger is getting on and off or moving in the vehicle, and the left and right vehicle heights 12a deviate from a preset reference range. While the vehicle is on the road, it is not determined whether or not the vehicle 1 is on a wavy road, and the left and right leveling controls at the rear of the vehicle 1 are maintained at the vehicle height at that point in a rest state. There is no worry that the vehicle height will change due to the control.

  Further, for example, the height of the road surface on which the front wheels on the left and right sides of the vehicle 1 are in contact with the ground is significantly higher than the other side, that is, the left and right vehicle heights at the front portion of the vehicle 1 detected by the front vehicle height sensor 11. The absolute value of the difference of 11a is equal to or greater than a preset first threshold value ΔF0 (see [Equation 1]), and the height of the road surface on which the rear wheel of the vehicle 1 comes into contact is determined on the other side of the vehicle 1 There is almost no difference in height on the left and right, which is equal to the height of the road surface on which the front wheels touch the ground. That is, the absolute value of the difference between the left and right vehicle heights 12a detected by the rear vehicle height sensor 12 and the reference vehicle height is determined in advance. Even in the case where it is less than or equal to the set second threshold value ΔR0 (see [Equation 3]), it is determined that the vehicle 1 is on a wavy road, and the left and right leveling controls at the rear of the vehicle 1 are forcibly suspended. Because crouching from this state When control is performed and compressed air is discharged simultaneously from the left and right front air springs at the front of the vehicle 1, the bump stopper built in the front air spring on one of the left and right sides is a top plate of the front air spring. The rubber contact state where it cannot be further contracted in the height direction by contact with the vehicle, and compressed air is continuously discharged from the front air springs on the other side of the left and right sides. Even if it is determined that not only the vehicle height 11a on the other side but also the vehicle height 12a on the left and right other side in the rear part of the vehicle 1 is lowered and the vehicle 1 is tilted and rolled to the other side, the vehicle 1 Compressed air is supplied to the front air spring on the left and right sides of the front and the rear air spring on the left and right sides of the rear of the vehicle 1. Not Rukoto, the vehicle 1 that, as the average value of the right and left vehicle height 11a at the front becomes high is avoided, and only crouching control is reliably performed alone.

  As a result, it is avoided that crouching control and leveling control are alternately performed so that control does not converge, and the vertical movement of the vehicle body continues until all the compressed air in the air tank is consumed. No longer occurs.

  Thus, even if the height of the road surface on which the front wheels of the vehicle 1 are in contact with the left and right is different, the right and left front wheels of the vehicle 1 can be prevented from floating and the crouching control can be performed reliably and the compression can be performed. Air consumption can be suppressed.

  Note that the vehicle air suspension control device of the present invention is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Front wheel 3 Rear wheel 4 Front air spring 5 Rear air spring 6 Air tank 8 Front vehicle height adjustment valve 8a Control signal 10 Rear vehicle height adjustment valve 10a Control signal 11 Front vehicle height sensor 11a Vehicle height 12 Rear vehicle height sensor 12a Vehicle High 13 Controller 14 Crouching switch

Claims (1)

A front air spring disposed to support a front wheel of the vehicle;
A rear air spring disposed to support the rear wheel of the vehicle;
A front vehicle height adjustment valve for supplying and discharging compressed air in an air tank to the front air spring;
A rear vehicle height adjustment valve for supplying and discharging compressed air in an air tank to the rear air spring;
A front vehicle height sensor for detecting left and right vehicle heights at the front of the vehicle;
A rear vehicle height sensor for detecting left and right vehicle heights at the rear of the vehicle;
By outputting control signals to the front vehicle height adjustment valve and the rear vehicle height adjustment valve based on the vehicle heights detected by the front vehicle height sensor and the rear vehicle height sensor, the vehicle heights at the left and right at the rear of the vehicle are set to a constant height In addition, leveling control is performed to keep the vehicle body parallel to the axle, and when passengers get on and off, crouching control is performed to lower the vehicle height at the front of the vehicle where the entrance is provided. A vehicle air suspension control device comprising a controller for performing vehicle height adjustment control for raising and lowering the vehicle to a required height,
During a normal mode in which the crouching control and the vehicle height adjustment control are not performed, the absolute value of the difference between the left and right vehicle heights detected by the front vehicle height sensor is greater than or equal to a preset first threshold value And the product of the difference between the left and right vehicle heights detected by the front vehicle height sensor and the difference between the left and right vehicle heights detected by the rear vehicle height sensor is negative. Or when the absolute value of the difference between the left and right vehicle heights at the rear part of the vehicle detected by the rear vehicle height sensor and the reference vehicle height is equal to or less than a preset second threshold value, the vehicle is on a wavy road A vehicle air suspension control device characterized in that it is configured to forcibly stop the left and right leveling controls at the rear of the vehicle.

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