Vehicle suspension apparatus

• US 4,697,237 A
• Filed: 11/14/1985
• Issued: 09/29/1987
• Est. Priority Date: 11/21/1984
• Status: Expired due to Term

• Current Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Original Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
• Inventors: Tanaka, Tadao, Kumagai, Naotake, Harara, Mitsuhiko, Taniguchi, Yasutaka, Tatemoto, Minoru, Suzumura, Masanaga
• Primary Examiner(s): Chin, Gary
• Application Number:
  US06/798,232
• Time in Patent Office: 684 Days
• Field of Search: 364/424, 364/425, 180/41, 280/6 H, 280/6 R, 280/6.1, 280/6.11, 280/707, 280/DIG. 1
• US Class Current: 701/38
• CPC Class Codes: B60G 17/0162 mainly during a motion involving steering operation, e.g. cornering, overtaking B60G17/0164 takes precedence
• CPC Class Codes: B60G 2400/821 Uneven, rough road sensing affecting vehicle body vibration
• CPC Class Codes: B60G 2500/30 Height or ground clearance
• CPC Class Codes: B60G 2600/02 Retarders, delaying means, dead zones, threshold values, cut-off frequency, timer interruption
• CPC Class Codes: B60G 2800/162 Reducing road induced vibrations

Abstract

A microcomputer performs roll control and communication control. In roll control, when the steering state detecting means and vehicle velocity detecting means detect a factor which causes a roll state of the vehicle body, a second control signal is produced to open desired supply and exhaust control valve so as to supply a preset amount of fluid to the fluid spring chambers of contracted suspension units and to exhaust a preset amount of fluid from the fluid spring chambers of stretched suspension units. In communication control, a first control signal is supplied to the communicating means to open the communication control valve when the steering state sensor detects that the steering angle falls within a preset steering angle and to close the communication control valve otherwise. After generation of the first control signal, when the steering state sensor detects that the steering direction of the steering wheel is in a return direction toward the neutral position and the steering angular velocity is lower than a preset steering angular velocity, a third control signal is supplied to the communicating means so as to open the communication control valve. When the steering state sensor detects, a third preset time after a second preset time from the generation of the third control signal, that the steering angle has reached the preset neutral range, a fourth control signal is produced to close the communication control valve for a fourth preset time.

Claims

1. A vehicle suspension appartus comprising:

fluid spring chambers arranged as suspension units for supporting respective vehicle wheels;

fluid supply means for supplying a fluid from each of said fluid spring chambers through exhaust control valve means;

fluid exhaust means for exhausting the fluid from each of said fluid spring chambers through exhaust control valve means;

communicating means for communicating each of said fluid spring chambers of the left suspension units with each of said fluid spring chambers of the right suspension units through communication control valve means;

steering state detecting means for detecting the steering state of a steering wheel;

roll control means for producing a second control signal for opening the desired one of said supply control valve means for a first preset time so as to supply a preset amount of a fluid to said fluid spring chambers of the contracted suspension units and opening the desired one of said exhaust control valve means for said first preset time so as to exhaust a preset amount of the fluid from said fluid spring chambers of the stretched suspension units when said steering state detecting means and vehicle velocity detecting means detect a factor with causes rolling of a vehicle body; and

communication control means for supplying a first control signal to said communicating means so as to open said communication control valve means when said steering state detecting means detects that the steering angle falls within a preset neutral range and to close said communication control valve means when said steering state detecting means detects that the steering angle falls outside the neutral range, said communication control means supplying a third control signal to said communicating means so as to open said communication control valve means when said steering state detecting means detects, after control by said roll control means, that the steering direction of said steering wheel is in a return direction toward a neutral direction and the steering angularly velocity is higher than a first preset steering angular velocity, and said communication control means supplying a fourth control signal to close said communication control valve means for a fourth preset time when said steering state detection means detect, during a third preset time period after a second preset time from production of the third control signal, that the steering angle falls within the neutral range.

2. A vehicle suspension apparatus according to claim 1, wherein said communication control means prohibits output of the fourth control signal when the vehicle velocity detected by said vehicle velocity detecting means is below a first preset vehicle velocity.

3. A vehicle suspension apparatus according to claim 1, wherein the first preset steering angular velocity for producing the third control signal by said communication control means is set to decrease when the vehicle velocity detected by said vehicle velocity detecting means increases.

4. A vehicle suspension apparatus according to claim 1, wherein said roll control means determines that the factor which causes rolling of the vehicle body is present when the steering angular velocity detected by said steering state detecting means is higher than a second preset steering angular velocity and the vehicle velocity detected by said vehicle velocity detecting means is higher than a second preset vehicle velocity.

5. A vehicle suspension apparatus according to claim 1, wherein said communicaton control means produces a fifth control signal for opening said communication control valve means when said steering state detecting means detects that the steering direction of said steering wheel is in the return direction toward the neutral position and the steering angular velocity is lower than the first preset angular velocity and when said vehicle velocity detecting means detects that the vehicle velocity is lower than a third preset vehicle velocity.

6. A vehicle suspension apparatus according to claim 1, wherein said communication control means and said roll control means comprise a controller with a microcomputer.

7. A vehicle suspension apparatus comprising:

fluid spring chambers arranged as suspension units for supporting respective vehicle wheels;

fluid supply means for supply a fluid to each of said fluid spring chambers through supply control valve means;

fluid exhaust means for exhausting the fluid from each of said fluid spring chambers through exhaust control valve means;

communicating means for communicating each of said fluid spring chambers of the left suspension units with each of said fluid spring chambers of the right suspension units through communication control valve means;

steering state detecting means for detecting the steering state of a steering wheel;

roll control means for producing a second control signal for opening the desired one of said supply control valve means for a first preset time so as to supply a preset amount of a fluid to said fluid spring chambers of the contracted suspension units and opening the desired one of said exhaust control valve means for said first preset time so as to exhaust a preset amount of the fluid from said fluid spring chambers of the stretched suspension units when said steering state detecting means and vehicle velocity detecting means detect a factor which causes rolling of a vehicle body; and

communication control means for supplying a first control signal to said communicating means so as to open said communication control valve means when said steering state detecting means detects the steering angle falls within a preset neutral range and to close said communication control valve means when said steering state detecting means detects that the steering angle falls outside the neutral range, said communication control means supplying a third control signal to said communicating means so as to open said communication control valve means when said steering state detecting means detects, after control by said roll control means, that the steering direction of said steering wheel is in a return direction toward a neutral position and the steering angular velocity is higher than a first preset steering angular velocity, said communication control means supplying a fourth control signal to close said communication control valve means for a fourth preset time when said steering state detecting means detects, during a third preset time period after a second preset time from production of the third control signal, that the steering angle falls within the neutral range, and said roll control means producing a fifth control signal for opening the desired one of said supply and exhaust control valve means for a fifth preset time so as to perform roll control in an opposite direction to that based on the second control signal supplied rom said communication control means, when said communication control means produces the fourth control signal.

8. A vehicle apparatus according to claim 7, wherein said roll control means determines that the factor which causes rolling of the vehicle body is present when the steering angular velocity detected by said steering state detecting means is higher than a second preset steering angular velocity and the vehicle velocity detected by said vehicle velocity detecting means is higher than a first preset vehicle velocity.

9. A vehicle suspension apparatus according to claim 7, wherein said communication control means produces a sixth control signal to open said communication control valve means when said steering state detecting means detects that the steering direction of said steering wheel is in the return direction toward the neutral position and the steering angular velocity is lower than the first preset steering annular velocity and said vehicle velocity detecting means detects that the vehicle velocity is lower than a second preset vehicle velocity.

10. A vehicle suspension apparatus according to claim 7, wherein said communication control means and said roll control means comprise a controller with a microcomputer.

11. A vehicle suspension apparatus comprising:

air spring chambers arranged as suspension units for supporting respective vehicle wheels;

air supply means for suppling air to each of said air spring chambers through supply control valve means;

air exhaust means for exhausting the air from each of said air spring chambers through exhaust control valve means;

communicating means for communicating said air spring chambers of the left suspension units with said air spring chambers of the right suspension units through communication control valve means;

steering state detecting means for detecting the steering state of a steering wheel;

roll control means for producing a second control signal for opening the desired one of said supply control valve means for a first preset time so as to supply a preset amount of air to said air spring chambers of the contracted suspension units and opening the desired one of said exhaust control valve means for said first preset time so as to exhaust a preset amount of the air from said air spring chambers of the stretched suspension units when said steering state detecting means and vehicle velocity detecting means detect a factor which causes a rolling of a vehicle body; and

communication control means for supplying a first control signal to said communicating means so as to open said communication control valve means when said steering state detecting means detects that the steering angle falls within a preset neutral range and to close said communication control vavle means when said steering state detecting means detects that the steering angle falls outside the neutral range, said communication control means supplying a third control signal to said communicating means so as to open said communication control valve means when said steering state detecting means detects, after control by said roll control means, that the steering direction of said steering wheel is in a return direction toward a neutral position and the steering angular velocity is higher than a first preset steering angular velocity, and said communication control means supplying a fourth control signal to close said communication control valve means for a fourth preset time when said steering state detecting means detects, during a third preset time period after a second preset time from production of the third control signal, that the steering angle falls within the neutral range.

12. A vehicle suspension apparatus according to claim 11, wherein said air supply means has a compressor and a first reserve tank for containing compressed air supplied from said compressor.

13. A vehicle suspension apparatus according to claim 12, wherein said air exhaust means has a second reserve tank for containing air exhausted from said air spring chambers, and a suction side of said compressor is connected to said second reserve tank.