KR910003764B1 - Vehicle suspension apparatus - Google Patents

Abstract

No content.

Description

Car suspension

1 is an overall configuration diagram showing a suspension device according to a first embodiment of the present invention.

2a and 2b show the operating state of the normally closed valve of FIG. 1, respectively.

3 is an overall configuration diagram showing an example different from the first embodiment.

4 is an open / closed state diagram of the height adjustment and attitude control of each solenoid valve of FIG.

5 is a flowchart for hard / soft switching of each suspension unit during roll control of the first embodiment.

FIG. 6 is a flowchart showing the hard / soft setting process according to the vehicle speed condition in step S12 of the flowchart of FIG.

FIG. 7 is a flowchart showing a process of roll control start determination in step S13 of the flowchart of FIG.

8 is a city diagram showing a vehicle speed-steering angle map.

9 is a diagram showing a vehicle speed-taking angle velocity map.

FIG. 10 is a flowchart showing a process of performing roll control in step S17 of the flowchart of FIG.

11 is a flowchart showing the process of roll control return determination in step S20 of the flowchart of FIG.

12 is a flowchart showing the second embodiment.

Fig. 13 is a flowchart showing the third embodiment.

14 is a flow chart showing a fourth embodiment.

15 is a flow chart showing a fifth embodiment.

16 is a flow chart showing a sixth embodiment.

17 is a flow chart showing a seventh embodiment.

18 is a flowchart showing the eighth embodiment.

19 is a flowchart showing the ninth embodiment.

20 is a flowchart showing another example of the roll control start determination process.

* Explanation of symbols for main parts of the drawings

SFL, SRL: Left wheel suspension unit SFR, SRR: Right wheel suspension unit

10: air spring 11: main air spring seal

12: air spring chamber 14: actuator

19: compressor 21: storage tank

221 to 224: Solenoid valve for air supply

241,242: Solenoid valve for communication

271 to 274: solenoid valve for exhaust

34: solenoid valve for hard / soft switching,

36: controller 41: vehicle speed sensor

42: steering sensor 43: steering wheel

44: acceleration sensor 45: garage selection switch

46: attitude control selector switch 48: brake sensor

50: engine speed detection sensor

The present invention relates to a vehicle suspension device having a height adjustment function.

In general, during turning of a vehicle or during slalom driving, rolls are generated in the vehicle body and steering stability is lost. Therein, a fluid spring is provided for each of the left and right suspension units, for example, when a roll occurs in the vehicle body, the fluid is set and supplied to the fluid spring chamber on the contraction side with respect to the roll direction, and the fluid is set from the fluid spring chamber on the expansion side. Suspension devices are contemplated that are configured to reduce the roll by ejecting.

Here, if the hardness of each suspension unit is increased when performing the roll control as described above, the roll control generated in the vehicle body can be reduced more reliably. On the other hand, in the roll control, the determination that ride comfort always deteriorates by that much. form.

The present invention has been devised in view of such a point, and its object is to increase roll hardness of each suspension unit only when necessary to perform roll control, thereby reducing rolls more reliably, otherwise softening the hardness of each suspension unit. The present invention provides a suspension device capable of performing roll control in a state where ride comfort is very good.

The present invention provides a fluid spring chamber installed in each of the left and right suspension units, a fluid supply means for supplying a fluid to each of the fluid spring chambers through a supply opening / closing valve, and a fluid opening / closing valve for discharging from the respective fluid spring chambers. Fluid discharge means for discharging the vehicle; driving condition detection means for detecting a driving condition of the vehicle; and detecting or predicting the occurrence of the body roll based on a signal from the driving condition detecting means. A suspension device for a vehicle having a control means having a control function for reducing a roll generated on a vehicle body by opening a supply opening / closing valve for a set time and opening the supply opening / closing valve for a fluid spring chamber on an extension side for a set time. Each suspending unit can be switched to either a hard state or a soft state. And hard / soft switching means for switching each of the suspension units to either a hard state or a soft state, wherein the control means has a running condition detected by the running condition detecting means and the operating condition of the roll control function. The hard / soft switching means controls the hard / soft switching means such that the respective suspension units are in a soft state when different setting conditions are satisfied, and the hard / soft switching means 14,34 so that the respective suspension units are in a hard state when they are not satisfied. The suspension device for a vehicle characterized by having a hard / soft control function for controlling a).

According to the present invention, the roll unit generated by the roll control function of the control means is reduced, and the suspension unit is switched to the hard state or the soft state by the hard / soft control function of the control means. Since the setting conditions for the hard / soft control switching are different from the operating conditions of the roll control function, even when the roll control is executed, each suspension unit should be made hard only when necessary according to the driving situation of the vehicle. It can be made soft.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, the first embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, SFR denotes a right front wheel suspension unit of an automobile, SRR denotes a right rear wheel suspension unit, and SRL denotes a left rear wheel suspension unit (SFR, SFL, SRR, SRL). Since each of these suspension units (SFR, SFL, SRR, SRL) has the same structure, only the suspension unit (SRL) shows the detailed structure here. The suspension unit SRL is composed of a main air spring chamber 11, a sub air spring chamber 12, a shock absorber 13, and a coil spring (not shown) used as an auxiliary spring.

14 is an actuator for switching the damping force of the shock absorber 13 to hard or soft. The actuator 14 rotates the damping force switching valve 14a together with the control rod 14b so that the first oil chamber 13a and the second oil chamber 13b, which are limited to each other by the piston, communicate with each other only through the orifice a. It selects in either of a state and the state which communicates through both orifice a1 and a2. In addition, by rotating the control rod 14b by the actuator 14, mutual communication and non-communication control between the main air spring chamber 11 and the sub air spring chamber 12 are simultaneously performed. Thereby, the hard or soft switching of the air spring is performed at the same time. In addition, control of the switching device is performed by the controller 36 provided with the microcomputer. 15 is a bellows that determines a part of the main air spring chamber 11.

16 is an air purifier, and the air supplied from the air purifier 16 is sent to the dryer 18 via the solenoid valve 17 for blocking air. The air dried by the dryer 18 is compressed by the compressor 19 and collected in the storage tank 21 via the check valve 20. Further, 191 is a compressor relay, which is controlled by the controller 36.

The storage tank 21 is connected to the main and sub air spring chambers 11 and 12 of each suspension unit via the air supply pipe 23 in which the air supply solenoid valves 221 to 224 are installed, respectively. In addition, the main and sub air spring chambers 11 and 12 of the suspension units SRL and SRR communicate with each other by a communication pipe 26 provided with a communication solenoid valve 242. In addition, the main and sub air spring chambers 11 and 12 of the suspension units SFL and SFR are communicated with each other by a communication pipe 25 provided with a communication solenoid valve 241.

Compressed air in the main and secondary air spring chambers 11 and 12 of each of the suspension units is exhaust pipe 28, check valve 29, dryer 18, solenoid provided with exhaust solenoid valves 271 to 274, respectively. It is discharged via the valve 17 and the air purifier 16.

The above-described air supply pipe 23 is provided with a pipe 31 in which the air supply side flow path selecting solenoid valve 30 is provided. When the solenoid valve 30 is closed, compressed air is supplied from the storage tank 21 to each suspending unit via the small diameter passage 33a, and when the solenoid valve 30 is opened, the storage tank 21 is opened. Compressed air is supplied from the small-diameter passage 31a and the large-diameter passage 31 toward both of the suspension units.

In addition, the exhaust pipe 28 is provided with a pipe 33 in which an exhaust-side flow path selection solenoid valve 32 is provided. When the solenoid valve 32 is closed, compressed air is discharged through the small diameter passageway 31a from the suspension unit to the dryer 18, and when the solenoid valve 32 is opened, the dryer ( 18, the compressed air is discharged through both the small-diameter passage 33a and the large-diameter passage 33.

A hard / soft switching solenoid valve 34 is provided between the air supply pipe 23 and each switching device, and the solenoid valve 34 is opened and closed by a signal from the controller 36.

In addition, the pressure in the storage tank 21 is detected by the pressure switch 35, and the detection signal of the pressure switch 35 is supplied to the controller 36. 37 is a pressure switch for detecting the internal pressures of the main and sub air spring chambers 11 and 12 of the rear suspension units SRL and SRR. The detection signal of this pressure switch 37 is supplied to the controller 36.

38F is installed between the lower arm 39 of the front right suspension of the car and the vehicle itself to detect the front garage of the vehicle, and 38R is installed between the side rod 40 of the rear left suspension of the vehicle and the vehicle body. It is a rear height sensor that detects the rear height of the car. The detection signals from these height sensors 38F and 38R are supplied to the controller 36. Both height sensor 38F, 38R can detect the distance from a low level, a middle level, and a high level, respectively.

41 is a vehicle speed sensor for detecting a vehicle speed, and 42 is a steering sensor for detecting a steering angle and a steering angle speed of the steering wheel 43. 44 is an acceleration sensor that detects acceleration in the front, rear, left, and right directions acting on the vehicle body. For example, when the acceleration is less than the set value, the sensor is further dropped, and the light from the light emitting diode is prevented by the shielding plate interlocked with the weight. This type of sensor is used to detect that the acceleration is less than the set value by blocking the photodiode and not reaching the photodiode, and that the acceleration or more of the set value is detected on the vehicle body by further inclining or moving. Thus, the detection signal detected by these sensors 41, 42, 43 is supplied to the controller 36.

45 is a garage selection switch for setting the target height to HIGH, LOW, or automatic garage adjustment, 46 is an attitude control selector for selecting to perform posture control to reduce the roll of the vehicle All. 47 is a hydraulic switch for detecting the hydraulic pressure of the lubricating oil of the engine, 48 is a brake sensor for detecting the amount of stepping of the brake, 49 is an accelerator opening sensor for detecting the accelerator opening of the engine, 50 is for detecting the rotational speed of the engine Engine rotational speed detection sensor, 51 is an engine switch for starting the engine, for example, an ignition switch, 52 is a shift position detection sensor for detecting the shift position of the transmission, 53 is a suspension unit (SFL, SFR, SRL, SRR) Hard selector switch for hard setting. The output signals of these switches 45, 46 and 51 and the detection signals of these sensors and switches 47, 48, 49, 50, 52 and 53 are supplied to the controller 36.

Also, solenoid valves 17,221 to 224,271 to 274,30,34 are normally closed valves, and solenoid valves 241 and 242 are normally open valves. 2A and 2B illustrate a normally closed valve, and FIG. 2A shows a state in which the valve is energized and is open, in which air is circulated as indicated by arrows a ₁ to a ₂ . The drawing indicates a state in which the valve is not energized, in which state the air flow is shut off. Although not shown for a normally open valve, it normally has the reverse operation of a closed valve.

FIG. 3 shows another example of the air piping of the above-mentioned suspension device. In this example, the storage tank 21 in FIG. 1 is divided into the front storage tank 21a and the rear storage tank 21b. divided. In addition, according to this, the air supply side flow path selection valve 30 is also divided into the front 30a and the rear 30b, and the hard / soft switching solenoid valve 34 is also the front 34a and the rear 34b. Are separated by).

Then, the controller 36 compares the target garage set by the garage selection switch 45 with the garage detected by the garage sensors 38F, 38R, and controls each solenoid valve in a direction in which the garage coincides with the target garage. Garage adjustments are made.

In addition, the attitude control function is achieved by the controller 36 sensing each posture change and its direction occurring in the vehicle body by each sensor and controlling each solenoid valve to cancel the posture change.

In addition, when the above-described height adjustment is performed, the garage is gradually changed by closing the air supply side flow path selection solenoid valve 30 and the exhaust side flow path selection solenoid valve 32, and thus the discomfort felt by the burner during the height adjustment. Is decreasing. In the above attitude control, by opening the air supply side flow path selection solenoid valve 30 and the exhaust side flow path selection solenoid valve 32, it is possible to sufficiently cope with a sudden attitude change.

In the apparatus shown in FIG. 1, the opening / closing state of each solenoid valve at the time of performing the above-described height adjustment and self-control function will be described with reference to FIG. 4 shows open / close states in the respective solenoid valves and respective modes shown in FIG. 1, in which O is ON and X is OFF.

In the normal mode, only the front and rear solenoid valves 241 and 242 for opening and closing are opened, whereby the air springs 10 of the left and right suspension units communicate with each other left and right, so that the volume of the air spring 10 is substantially reduced. Since the spring constant decreases, the riding comfort can be improved.

The garage adjustment mode compares the garage signal detected by the garage sensors 38F and 39R with the target garage set by the garage select switch 45, and control is performed toward the target garage. When the solenoid valve is in the garage lowering control, the required exhaust solenoid valve is opened. In addition, in this height adjustment mode, communication solenoid valves 241 and 242 are opened, thereby maintaining a good ride comfort. In addition, the air supply side flow path selection solenoid valve 30 and the exhaust side flow path selection solenoid valve 32 are closed in this height adjustment mode, and are comprised so that the height adjustment may be made gradually and it will not be uncomfortable to a person who rides.

The roll control is a start mode in which the required air is supplied to the air spring 10 on the contraction side in the left and right direction and the required air is exhausted from the other air spring 10, and the state obtained by the start mode. And a return mode in which the left and right air springs 10 achieve the same pressure with each other when the cause of the roll disappears.

In the start mode, the air supply solenoid valve and the exhaust solenoid valve, which are required at the same time as closing the left and right communication solenoid valves 241 and 242, are opened for a predetermined time. At the same time, each flow path selector solenoid valve (30, 32) is opened. Accordingly, the posture control is quickly performed. In the holding mode, only the solenoid valve for selecting each channel continues to be opened.

In this way, for example, when the lateral acceleration acting on the vehicle body increases during turning, the air supply to one air spring 10 and the air exhaust from the other air spring need to be added. This additional control can be performed as quickly as possible. In the return mode, only the left and right angle solenoid valves 241 and 242 open, thereby returning to the same state as the normal mode.

The braking control (noise dive control) is a start mode for supplying the compressed air to the air spring 10 on the front side and exhausting the compressed air from the air spring 10 on the rear side. In the holding mode which maintains the obtained state, and when there is no immersion of the front part of the vehicle body by braking, a small amount of compressed air is exhausted from the front air spring 10 and compressed air is fed to the rear air spring 10. It is composed of return mode for supplying required air.

In the start mode, the front-side air supply solenoid valves 223 and 224 and the rear-wheel exhaust solenoid valves 271 and 272 are opened for a predetermined time, and each flow path selection solenoid valve is opened. In the holding mode, only the flow path selection solenoid valve continues in the open state as in the roll control described above. In the return mode, the solenoid valves 273 and 274 for the front wheel exhaust and the solenoid valves 221 and 222 for the rear wheel supply are opened only for a set time, and the solenoid valves 30 and 32 for selecting each channel continue to be opened during this time. do.

Acceleration control (squat control) is a start mode in which the required air is exhausted from the air spring 10 on the front side and the required air is exhausted from the air spring 10 on the rear side. In the holding mode for maintaining the state and when the rear portion of the vehicle body due to acceleration is not settled, the required air is exhausted from the rear air spring 10 and the compressed air is moved to the front air spring 10 at the same time. It is composed of the return mode for supplying the required amount.

In the start mode, the front wheel side solenoid valves 273 and 274 and the rear wheel side solenoid valves 221 and 222 are opened for a predetermined time, and the respective channel selection solenoid valves are opened. As for the holding mode, each solenoid valve for selecting a flow path continues in the open state similarly to the roll control described above. In the return mode, the front-side air supply solenoid valves 223 and 224 and the rear-wheel exhaust solenoid valves 271 and 272 are opened only for a set time, while the respective channel selection solenoid valves 30 and 32 are kept open. do.

Next, specific control by the controller 36 in the first embodiment will be described with reference to FIGS. 5 to 11.

FIG. 5 is a flowchart for hard / soft switching of each suspending unit during roll control, FIG. 6 is a flowchart showing processing of hard / soft setting according to the vehicle speed condition in step S12 of FIG. 5, and FIG. Fig. 8 is a flowchart showing the process of roll control start determination in step S13 of the flowchart, Fig. 8 is a view showing a vehicle speed steering angle map, Fig. 9 is a view showing a vehicle speed steering angle speed map, Fig. 10 The flowchart which shows the process of roll control implementation in step S17 of the flowchart of FIG. 5, and FIG. 11 is the flowchart which shows the process of roll control return determination in step S20 of the flowchart of FIG.

First, the control content will be described according to the flowchart shown in FIG.

First, when the ignition switch is turned on, the damping force drive circuit is turned on in step S1. Next, the flow advances to step S2, and it is determined whether the present is under control. If NO is determined in step S2, the flow advances to step S3, where a hard / soft setting flow is performed according to the vehicle speed condition shown in detail in FIG.

Here, the detail of the process of step S3 is demonstrated according to FIG. 6 as follows.

First, in step S21, the controller 36 determines whether or not the hard selection switch 53 is turned on.

When it is determined "NO" in this step S21, it is determined in step S22 whether the vehicle speed detected by the traveling vehicle speed sensor 41 is 100 km / h or more. It is determined as "Yes" in this step S22, or "Yes" in step S21. The flow advances to step S23. In step S23, the controller 36 opens the hard / soft switching solenoid valve (hereinafter referred to as H / S switching valve) 34. Accordingly, since the compressed air of the storage tank 21 operates the actuator 14 via the H / S switching valve 34, the main air spring chamber 11 and the sub air spring chamber 12 of each suspension unit are different from each other. The spring constant rises due to non-communication, and at the same time, the first oil chamber 13a and the second oil chamber 13b of the shock absorber 13 of each suspension unit communicate with each other only through the orifice a. The unit goes into a hard state.

On the other hand, if it is determined "NO" in step S22, it progresses to step S24 and it is determined whether the vehicle speed detected by the vehicle speed sensor 41 is 90 km / h or less. In step S24, "No", that is, when the vehicle speed is less than 100 km / h and higher than 90 km / h, the flow proceeds to step S25. In this step S25, it is determined whether each suspension unit is currently set to the hard state. If NO is determined in step S25 or YES in step S24, the flow proceeds to step S26. The controller 36 closes the H / S switching solenoid valve 34. Accordingly, since the actuator 14 becomes inoperative, the main air spring chamber 111 and the sub air spring chamber 12 of each suspending unit are in a communication state, and the spring constant drops, and the shock absorber 13 of each suspending unit simultaneously. The first and second oil chambers 13a and 13b communicate with each other via the orifices a _{1 and} a _2, so that the damping force is lowered. As a result, each suspension unit is in a soft state.

In this way, when the vehicle speed is 100 km / h or more at high speed, each suspension unit is switched to the hard state, so that the running stability at high speed is greatly improved. Furthermore, after each suspension unit is switched to the hard state because the vehicle speed is 100km / h or more, the control unit does not switch to the soft state unless the vehicle speed is lowered below 90km / h. Hunting can be prevented.

Returning to Fig. 5, the description of the flowchart shown in Fig. 5 is continued.

If the process of step S3 is executed or it is determined "Yes" in step S2, it progresses to step S4 and the roll control start determination flow which shows the detail in FIG. 7 is performed.

Here, the content of the flowchart shown in FIG. 7 is demonstrated as follows.

First, in step S31, the vehicle speed detected by the vehicle speed sensor 41 and the steering angle and the steering angle speed detected by the steering sensor 42 are introduced into the controller 36. Next, the process proceeds to step S32, in which the vehicle speed-steering angle map shown in FIG. 8 stored in the controller 36 is determined in accordance with the vehicle speed and steering angle (determining the time for opening each valve based on the vehicle speed and steering angle). With reference to the map, it is determined whether the current vehicle speed-steering angle belongs to areas I to III (area under which posture control is performed) or belongs to a dead zone (area without posture control) in this map. Further, the control areas I to III described above are set such that control time t1 to t3 corresponding to the degree of roll generated by the vehicle speed and steering angle at that time are obtained.

If it is determined in the step S32 that it belongs to the control areas I to III, the flow advances to step S33 to be the roll control flag "1". At the same time, the steering direction of the steering wheel 43 is determined and stored in a predetermined memory area in the controller 36 together with the control time determined by the control areas I to III, respectively.

On the other hand, if it is determined in step S32 that it belongs to the dead zone, the process proceeds to step S34. In this step S34, the vehicle speed-steering angular velocity map shown in FIG. 9 stored in the controller 36 based on the vehicle speed and the steering angle speed (map for determining the opening time of each valve based on the vehicle speed and the steering angle speed) is referred to. Then, it is determined whether the current vehicle speed-steering angular velocity belongs to region I-III (region in which posture control is performed) or dead zone (region in which posture control is not performed) in the map. Incidentally, the control areas I to III described above are set such that control time t1 to t3 corresponding to the degree of roll caused by the vehicle speed and the steering angle are obtained.

If it is determined in step S34 that it belongs to the control areas I to III, it proceeds to step S35 and it is determined whether the steering direction of the steering wheel 43 is returning, ie, toward the neutral position. If NO is determined in step S35, the flow proceeds to step S33. In addition, if it determines with "Yes" in step S35 or belonging to a dead zone area in step S34, it is determined that posture control is not necessary and it progresses to step S5 of FIG.

It returns to FIG. 5 again, and continues description of the flowchart shown in FIG.

In step S5, it is determined whether roll control flag "1" was made in step S33 this time, ie, whether roll control is necessary. When it is determined "Yes" in step S5, it progresses to step S6 and it is determined whether a vehicle speed is more than predetermined preset vehicle speed (for example, 70 km / h).

In step S6, "YES", that is, when the driving condition requires roll control and the vehicle speed is determined to be equal to or higher than the set vehicle speed, the flow proceeds to step S7, where the H / S selector valve 34 is controlled by the controller 36. Is opened by. Accordingly, the actuator 14 is operated so that the spring force and the damping force of each suspension unit are set to the hard state.

On the other hand, in step S15, even if no, i.e., even if the vehicle speed is determined to be less than the set vehicle speed even in the traveling situation in which roll control is required, the flow advances to step S8 to determine whether the hard selection switch 53 is turned on. If it is determined "Yes" in this step S8, it will progress to step S7. If NO is determined in step S8, the flow advances to step S9 to close the H / S switching valve 34 under the control of the controller 36. As a result, the actuator 14 is deactivated, and the spring force and the damping force of each suspension unit are set to the soft state.

When this process of step S9 or above-mentioned step S7 is performed, it progresses to step S10 and the roll control implementation flow which shows the detail in FIG. 10 is performed.

Here, the content of the flowchart shown in FIG. 10 is demonstrated as follows.

First, in step S41, it is determined whether or not this roll control is performed based on the control area of the vehicle speed-steering angular velocity map shown in FIG. If it is determined in step S41 that the roll control is executed due to the quick steering of the steering wheel 43, for example, the flow advances to step S42 in order to perform the quick roll control in response to the flow path selection solenoid valve ( 30 and 32 are opened by the control of the controller 36.

On the other hand, if it is determined in step S41 that the steering wheel 43 is gradually steered based on "no", that is, the control area of the vehicle speed-steering angle map shown in FIG. 8, roll control is gradually performed in response to this. In order to perform the following roll control, the flow advances to step S43, and the respective flow path selection solenoid valves 30 and 32 are closed by the control of the controller 36.

When the process of step S43 or the above-described step S44 is executed, the process proceeds to step S44 and the respective communication valves 241 and 242 are closed by the control of the controller 36, and the suspension unit SFL communicates with the SFR and the SRL and SRR communication. Block communication. When the process of step S44 is performed, it progresses to step S45 and it determines in which direction the steering wheel 43 is steered.

When it determines with steering in the right direction R in this step S45, it progresses to step S46. In step S46, the solenoid valves 221 and 223 on the left wheel side are opened by the control of the controller 36 for the control time t stored in step S33 of the flowchart of FIG. ) Is opened by the control time t. Accordingly, the set amount of compressed air from the storage tank 21 is supplied to the air spring 10 of the left wheel side suspension units SFL and SRL and from the air spring 10 of the right wheel suspension units SFR and SRR. The set amount of compressed air is discharged through the dryer 18 to the air purifier 16. As a result, the steering wheel 43 can be steered to the right to control the roll in the left direction to be generated in the vehicle body.

In addition, when it determines with steering to the left direction L in step S45, it progresses to step S47. In step S47, the control of the controller 36 opens the right side air supply solenoid valves 222, 224 for the control time t stored in step S33 of the flowchart of Fig. 7, and at the same time the solenoid valve for exhaust on the left side wheel ( 271, 273 are opened by the control time t. Accordingly, the air spring 10 of the right side suspension unit SFR, SRR is supplied with a predetermined amount of compressed air from the storage tank 21, and the air spring 10 of the left side suspension unit SFL, SRL is supplied. The compressed air is discharged from the set amount through the dryer 18 to the air purifier 16. As a result, by steering the steering wheel 43 to the left, the roll in the right direction to be generated in the vehicle body can be controlled. When the processing of step S46 or step S47 is executed, the flow returns to the return shown in FIG. 5, that is, step S2, and the following situation change is observed.

Return to the fifth road and continue the flowchart depicted in this fifth view.

If NO is determined in step S5, that is, there is no need for roll control in step S4, the flow proceeds to step S11, and a roll control return determination flow showing the details in FIG. 11 is executed.

Here, the content of the flowchart shown in FIG. 11 is demonstrated as follows.

First, it is determined whether the steering angle θ detected by the steering sensor 42 in step S51 is equal to or less than the predetermined steering angle θ ₀ . When it is determined "Yes" in this step S53, it progresses to step S52 and becomes roll control flag "0", and it progresses to step S12 of the flowchart of FIG. If NO is determined in step S51, the flow advances to step S53 to determine whether the vehicle speed detected by the vehicle speed sensor 41 is greater than the preset vehicle speed (for example, 20 km / h). If it is determined in step S53 that no "no", that is, the steering angle 43 of the steering wheel 43 is _greater than the set steering angle θ ₀ , the magnetic flux is smaller than the set magnetic flux, then the flow proceeds to step S52. In addition, in step S53, when the steering wheel angle steering angle (theta) of steering wheel is larger than setting steering angle (theta) ₀ and vehicle speed is larger than setting vehicle speed, it progresses to step S12 of the flowchart of FIG.

Returning to FIG. 5 again, the description of the flowchart shown in FIG. 5 is continued.

In step S12, it is determined whether the roll control flag is "0". If it is determined "Yes" in this step S12, control is made to return to step S13 and roll control will be performed. That is, in step S13, the communication solenoid valves 241 and 242 are opened by the control of the controller 36, and the air spring 10 of the left wheel suspension units SFL and SFR and the right wheel suspension units SRL and SRR are opened. Air spring 10 is in communication with each other, and each suspension unit is returned to the state before roll control.

As described above, according to the first embodiment, the roll of the vehicle body generated at the time of turning driving can be effectively suppressed, and the following effects can be obtained. Furthermore, as apparent in the processing of steps S6 to S9 in FIG. 5, when the vehicle speed is equal to or higher than the set vehicle speed V0 km / h (for example, 70 km / h), each suspension unit is set to soft to perform roll control. In the case of the set vehicle speed V0 km / h or less, each suspension unit is set to hard to perform roll control. Therefore, for example, at a vehicle speed of 70 km / h or more, the rolls generated in the vehicle body can be suppressed more reliably, and at a vehicle speed of 70 km / h or less, the roll can be reduced while maintaining a good ride comfort. In other words, it is possible to maximize the contrary action of the steering stability and ride comfort.

Next, a second embodiment of the present invention will be described with reference to FIG. This second embodiment basically has the same configuration as the first embodiment, and differs from the first embodiment in that the first embodiment differs between steps S5 and S6 of the flowchart shown in FIG. In the step S100 is set.

In step S100, it is determined in step S4 whether the vehicle speed steering angle map has become a roll control flag by the control area. And if it is determined "Yes" in this step S100, it will progress to step S100 and the process similar to 1st Example mentioned above is performed. If NO is determined in step S100, the flow advances to step S7 to set the suspension unit hard.

Therefore, according to this second embodiment, when roll control is performed by the control area of the vehicle speed-steering angle speed map, each suspension unit is unconditionally switched to hard, and the roll control is controlled by the control area of the vehicle speed-steering angle map. If the vehicle speed is higher than the set speed, switch each suspension unit to hard. Otherwise, switch each suspension unit to soft. In other words, according to the second embodiment, in the case of roll control performed when the steering wheel 43 is steered steeply, each suspension unit is necessarily switched to hard, and the roll control when the steering wheel 43 is steered gradually. In the case where the vehicle speed is higher than or equal to the set vehicle speed, each suspension unit can be set to be switched to hard.

Next, the third embodiment of the present invention will be described with reference to FIG. This third embodiment basically has the same configuration as that of the first embodiment, and differs from the first embodiment in that the first embodiment differs between steps S5 and S6 of the flowchart shown in FIG. It is in the point which installed step S101.

In step S101, it is determined in step S4 whether the roll control flag is set by the control area of the vehicle speed-steering angular velocity map. If it is determined in step S101 that 7 is "Yes", the process proceeds to step S6 and the same processing as in the first embodiment described above is performed. If NO is determined in step S101, the flow proceeds to step S8.

Therefore, according to this third embodiment, each suspension unit is switched to hard only when the vehicle speed-steering angle speed map is controlled by the control area and the vehicle speed is equal to or higher than the set vehicle speed. Switch to soft. In other words, according to this third embodiment, it is possible to obtain a setting that each suspension unit is switched to hard only when the steering wheel 43 is steered in a state where the vehicle speed is higher than or equal to the set vehicle speed.

Next, a fourth embodiment of the present invention will be described with reference to FIG. This fourth embodiment basically has the same configuration as in the first embodiment, and differs from the first embodiment in that the step S102 is used instead of the step S6 of the flowchart shown in FIG. 5 in the first embodiment. Is at the point set.

In step S102, it is determined in step S4 whether or not the roll control flag is set by the control area of the vehicle speed-steering angle map. And if it is determined "Yes" in this step S102, it will progress to step S8. If NO is determined in step S102, the flow proceeds to step S7.

Therefore, according to this fourth embodiment, when roll control is performed by the control area of the vehicle speed-steering angle speed map, each suspension unit is unconditionally switched to hard. In other words, according to the fourth embodiment, it is possible to obtain a setting that each suspension unit is switched to this hardware only when the steering wheel 43 is steered steeply.

Next, the fifth embodiment of the present invention will be described with reference to FIG. This fifth embodiment basically has the same configuration as that of the fourth embodiment, and differs from the fourth embodiment between the steps S102 and S8 of the flowchart shown in FIG. 14 in the fourth embodiment. In the step S103 is set.

In step S103, it is determined whether the control time obtained by the vehicle speed-steering angle map in step S4 is equal to or less than the preset control time t0 seconds. And if it is determined "Yes" in this step S103, it will progress to step S8. If NO is determined in step S103, the flow proceeds to step S7.

Therefore, according to the fifth embodiment, when roll control is performed by the control area of the vehicle speed-steering angle speed map, each suspension unit is unconditionally switched to hard, and roll control is performed by the control area on the vehicle speed-steering angle map. In the case where temporary acceleration is performed, each suspension unit is switched to hard only when the control time determined by the vehicle speed-steering angle map exceeds the set time t0. Otherwise, each suspension unit is switched to soft. In other words, according to the fifth embodiment, the roll control is performed when the steering wheel 43 is steered steeply, and each suspension unit is necessarily switched to hard, and is performed when the steering wheel 43 is steered. In roll control, it is possible to obtain the setting that each suspension unit switches to hard only when the control time t0 exceeds the set control time t0 seconds.

Next, a sixth embodiment of the present invention will be described with reference to FIG. This sixth embodiment basically has the same structure as the fifth embodiment, and differs from the fifth embodiment in that the fifth embodiment replaces step S104 in place of step S102 of the flowchart shown in FIG. It is at a set point.

In step S104, it is determined whether or not the control time obtained by the vehicle speed-steering angular velocity map in step S4 is equal to or less than the preset control time t0 seconds. And if it is determined "Yes" in this step S104, it will progress to step S8. If NO is determined in step S104, the flow proceeds to step S7.

Therefore, according to this sixth embodiment, the roll control is performed by the control area of the vehicle speed-steering angle speed map, and each suspension unit is switched to hard only when the control time exceeds the set time t0 seconds. In this case, switch each suspension unit to soft. In other words, according to the sixth embodiment, the steering wheel 43 is steered steeply so that the setting that each suspension unit switches to hard only when the control time at the time exceeds the set control time t0 seconds can be obtained.

Next, the seventh embodiment of the present invention will be described with reference to FIG. This seventh embodiment basically has the same configuration as in the first embodiment, and differs from the first embodiment in that the step S105 is used instead of the step S6 of the flowchart shown in FIG. 5 in the first embodiment. Is at the point set. In this seventh embodiment, for example, a differential transformer-type sensor G that can detect the magnitude of plasticity is used as the acceleration sensor 44.

In this step S105 it is determined whether the acceleration in the horizontal direction detected by the acceleration sensor 44 is a preset acceleration G greater than or equal to _zero. And if it is determined "Yes" in this step S105, it will progress to step S7. If NO is determined in step S104, the flow proceeds to step S8.

Therefore, according to the seventh embodiment, when the roll control is performed, each suspension unit is switched to hard only when the acceleration detected by the acceleration sensor is _{equal to} or higher than the set acceleration G ₀ , and in other cases, each suspension unit is changed to software. Switch. In other words, according to the sixth embodiment, the steering wheel 43 is steered and a setting in which each suspension unit is switched hard only when the acceleration in the lateral direction at that time is large can be obtained.

Next, an eighth embodiment of the present invention will be described with reference to FIG. This eighth embodiment is basically the same as the seventh embodiment described above, and differs from the seventh embodiment in that the seventh embodiment includes steps S5 and step of the flowchart shown in FIG. 17. It is in the point which set S106 between S105.

In step S106, it is determined in step S4 whether the roll control flag is set by the control area of the vehicle speed-steering angle map. And if it is determined "Yes" in this step S106, it will progress to step S105. If NO is determined in step S106, the flow proceeds to step S7.

Therefore, according to this eighth embodiment, when roll control is performed by the control area of the vehicle speed-steering angle speed map, each suspension unit is unconditionally switched to hard, and the roll control is controlled by the control area of the vehicle speed-steering angle map. Is carried out, the lateral direction switches to hard when the acceleration is equal to or higher than the set acceleration G0. Otherwise, each suspension unit is switched to soft. In other words, according to the sixth embodiment, in the roll control performed when the steering wheel 43 is steered steeply, each suspension unit is switched to hard, and in the roll control when the steering wheel 43 is steered slowly, Only when the acceleration in the transverse direction is large, the setting that each suspension unit switches to hard can be obtained.

Next, a ninth embodiment of the present invention will be described with reference to FIG. This ninth embodiment has the same configuration as the eighth embodiment described above, and differs from the eighth embodiment in that the eighth embodiment replaces step S106 of the flowchart shown in FIG. 18 in the eighth embodiment. It is at the point where S107 is set.

In step S107, it is determined in step S4 whether the roll control flag is set by the control area of the vehicle speed-steering angular velocity map. And if it is determined "Yes" in this step S107, it will progress to step S105. If NO is determined in step S107, the flow proceeds to step S8.

Therefore, according to this ninth embodiment, the roll control is performed by the control area of the vehicle speed-steering angular velocity map, and each suspension unit is switched to hard only when the acceleration in the lateral direction is equal to or higher than the set acceleration G0. Switch the suspension unit to soft. In other words, according to this seventh embodiment, when the steering wheel 43 is steered steeply, it is possible to obtain the setting that each suspension unit is switched to hard only when the lateral acceleration at that time is large.

20 shows a modification of the process of roll control start determination shown in FIG.

The different point of the flowchart shown in FIG. 7 in the modification shown in FIG. 20 is as follows. That is, in this modification, steps S108 to S111 are set instead of steps S32, S34, and step S35 in the flowchart shown in FIG.

In step S108, it is determined whether the steering angle speed is larger than the set steering angle speed. If NO is determined in step S108, the flow proceeds to step S109. In step S109, similarly to step S32 of the flowchart of FIG. 7, the vehicle speed-steering angle map shown in FIG. 8 stored in the controller 36 based on the vehicle speed and steering angle is referenced, and the current vehicle speed-steering angle is referred to. In this map, it is determined whether they belong to the regions I to III or belong to the dead zone.

If it is determined in step S109 that it belongs to the control areas I to III, the flow advances to step S33. If it is determined in step S109 that it belongs to the dead zone, the flow proceeds to step S5 of FIG.

On the other hand, if it is determined "Yes" in step S108, the vehicle speed shown in FIG. 9 stored in the controller 36 based on the vehicle speed and the steering angle speed in step S110, similarly to step S34 of the flowchart of FIG. The steering angular velocity map is referenced, and it is determined whether the current vehicle speed-steering angular velocity belongs to the regions I to III or the dead zone range in this map.

If it is determined in step S110 that it belongs to the control areas I to III, the flow advances to step S111. In step S111, it is determined whether or not the steering direction of the steering rear work 43 is returned, that is, directed to the neutral position. If NO is determined in step S111, the flow proceeds to step S33. If YES is determined in step S111, the flow proceeds to step S5 of FIG.

The modifications shown in FIG. 20 as described above can also achieve almost the same effects as the processing of the flowchart shown in FIG.

Further, in each of the above embodiments, the hard / soft switching of each suspension unit is made by switching both of the damping force and the spring constant of each suspension unit, but the present invention provides only switching of the damping force of each suspension unit or only the spring constant. It is also possible to configure to perform the switching of.

In each of the above embodiments, the present invention is applied to an air suspension apparatus using air pressure, but the present invention can be similarly applied to a suspension apparatus of, for example, a pneumatic type.

As described above, according to the present invention, when performing roll control, each suspension unit is switched to hard only when necessary on the basis of the traveling situation detected by the traveling situation detecting means, so that the roll is more reliably obtained. Otherwise, each suspension unit is switched to soft, and thus a suspension device capable of performing roll control with a very comfortable ride can be obtained.

Claims (1)

Fluid spring chambers 11 and 12 installed in the left and right suspension units SFR, SFL, SRR and SRL, respectively, and on / off valves 221, 222, 223 and 224 for supplying the fluid spring chambers 11 and 12, respectively. Fluid supply means (19, 21, 23) for supplying a fluid through the) and the fluid through the discharge opening and closing valve (271, 272, 273, 274) from the fluid spring chamber (11, 12) When the fluid discharge means 28 detects or predicts the occurrence of the vehicle body roll on the basis of the signals from the driving condition detecting means 41, 42, 44 for detecting the running condition of the vehicle and the running condition detecting means, Supply opening / closing valves 221, 223 to 222 and 224 for the fluid spring chambers 11 and 12 of the fluid spring chamber 11, 12 of the fluid spring chambers 11 and 12 on the extension side The control means 36 having a control function of reducing the rolls of the vehicle body by opening the (221, 222 or 223, 224) for a set time are obtained. In a vehicle suspension apparatus, each of the suspension units SFR, SFL, SRR, SRL is configured to allow engagement in either a hard state or a soft state, and at the same time, each of the suspension units SFR, SFL, SRR, SRL. Has hard / soft switching means (14,34) for switching to either a hard state or a soft state, and wherein the control means has a running state detected by the running state detecting means (41, 42, 44). When the setting conditions different from the operating conditions of the control function are satisfied, the hard / soft switching means 14, 34 are controlled so that the respective suspension units SFR, SFL, SRR, SRL are in a soft state, and they are not satisfied. And a hard / soft control function for controlling the hard / soft switching means (14,34) such that each of the suspension units (SFR, SFL, SRR, SRL) is in a hard state.

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