US4897776A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic controlled fluid suspension system for controlling roll and pitch of a vehicle body
Assignee: Toyota Motor Corp
•
Filing: 1988-09-02
•
Granted: 1990-01-30
•
Expires: 2008-09-02
Abstract
Abstract In controlling roll and pitch of a vehicle body responsive to a displacement signal produced at each wheel of the vehicle, each signal is low-pass-filtered with a certain threshold frequency to prevent hunting of the control due to an excessively high frequency component (such as noise or a component corresponding to road irregularities) of the signal. According to this invention, the threshold frequency is changed to a higher value in order to get quick attitude control when the roll or pitch of the body is expected, while it is set at a lower value when no such attitude change is expected in order to prevent hunting of the control.
Inventors
- 👤 Shingo Urababa
- 👤 Shuuichi Buma
- 👤 Toshio Aburaya
- 👤 Takashi Yonekawa
- 👤 Osamu Takeda
- 👤 Shunichi Doi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:31
CPC Classifications
B; B60; B60G; B60G17/00; B60G17/015; B60G17/016; B60G2500/00; B60G2500/20; B60G2500/201; B60G2500/2014
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
208 words
An electronic controlled fluid suspension system for a vehicle comprising: a fluid suspension provided for each of a plurality of wheels of the vehicle; a height detection means provided for each of the plurality of wheels for detecting a height of a body of the vehicle at said each wheel and for generating a height signal; a roll detection means responsive to the height signals for generating a roll signal representing a roll of the body; a low-pass filtering means for passing only a component of the roll signal having a frequency lower than a threshold frequency; a driving state detection means for detecting driving parameters that affect a lateral acceleration of the body; a threshold changing means responsive to the detected driving parameters for changing the threshold frequency of the low-pass filtering means to a higher value when the body is expected to develop a roll; a target determination means for determining a target roll signal; an attitude control means for generating a control amount in order to feedback-control the roll signal filtered by the low-pass filtering means to approach the target roll signal; and a fluid flow control means responsive to the control amount for controlling fluid flow to and from each of the fluid suspensions.
Claim 2
Dependent Claim
208 words
An electronic controlled fluid suspension system for a vehicle comprising: a fluid suspension provided for each of a plurality of wheels of the vehicle; a height detection means provided for each of the plurality of wheels for detecting a height of a body of the vehicle at said each wheel and for generating a height signal; a roll detection means responsive to the height signals for generating a roll signal representing a roll of the body; a low-pass filtering means for passing only a component of the roll signal having a frequency lower than a threshold frequency; a driving state detection means for detecting driving parameters that affect a lateral acceleration of the body; a threshold changing means responsive to the detected driving parameters for changing the threshold frequency of the low-pass filtering means to a higher value when the body is expected to develop a roll; a target determination means for determining a target roll signal; an attitude control means for generating a control amount in order to feedback-control the roll signal filtered by the low-pass filtering means to approach the target roll signal; and a fluid flow control means responsive to the control amount for controlling fluid flow to and from each of the fluid suspensions.
Claim 3
Dependent Claim
69 words
The electronic controlled fluid suspension system according to claim 1, wherein: the driving state detection means comprises a means for detecting a running speed of the vehicle and a means for detecting a steering angle of the vehicle; and the threshold changing means changes the threshold frequency when the detected running speed is greater than a reference speed and the detected steering angle is greater than a reference angle.
Claim 4
Dependent Claim
74 words
The electronic controlled fluid suspension system according to claim 2, wherein: the electronic controlled fluid suspension system further comprises a lateral acceleration detection means for detecting said lateral acceleration of the body; and the target determination means comprises a means for determining the target roll signal according to the detected lateral acceleration, and a means for setting the target roll signal at zero when the detected lateral acceleration is greater than a predetermined value.
Claim 5
Dependent Claim
208 words
An electronic controlled fluid suspension system for a vehicle comprising: a fluid suspension provided for each of a plurality of wheels of the vehicle; a height detection means provided for each of the plurality of wheels for detecting a height of a body of the vehicle at said each wheel and for generating a height signal; a pitch detection means responsive to the height signals for generating a pitch signal representing a pitch of the body; a low-pass filtering means for passing only a component of the pitch signal having a frequency lower than a threshold frequency; a driving state detection means for detecting driving parameters that affect a longitudinal acceleration of the body; a threshold changing means responsive to the detected driving parameters for changing the threshold frequency of the low-pass filtering means to a higher value when the body is expected to develop a pitch; a target determination means for determining a target pitch signal; an attitude control means for generating a control amount in order to feedback-control the pitch signal filtered by the low-pass filtering means to approach the target pitch signal; and a fluid flow control means responsive to the control amount for controlling fluid flow to and from each of the fluid suspensions.
Claim 6
Dependent Claim
208 words
An electronic controlled fluid suspension system for a vehicle comprising: a fluid suspension provided for each of a plurality of wheels of the vehicle; a height detection means provided for each of the plurality of wheels for detecting a height of a body of the vehicle at said each wheel and for generating a height signal; a pitch detection means responsive to the height signals for generating a pitch signal representing a pitch of the body; a low-pass filtering means for passing only a component of the pitch signal having a frequency lower than a threshold frequency; a driving state detection means for detecting driving parameters that affect a longitudinal acceleration of the body; a threshold changing means responsive to the detected driving parameters for changing the threshold frequency of the low-pass filtering means to a higher value when the body is expected to develop a pitch; a target determination means for determining a target pitch signal; an attitude control means for generating a control amount in order to feedback-control the pitch signal filtered by the low-pass filtering means to approach the target pitch signal; and a fluid flow control means responsive to the control amount for controlling fluid flow to and from each of the fluid suspensions.
Claim 7
Dependent Claim
80 words
The electronic controlled fluid suspension system according to claim 4, wherein: the driving state detection means comprises a means for detecting an operation of a brake pedal of the vehicle and a means for detecting a throttle valve opening speed of an internal combustion engine of the vehicle; and the threshold changing means changes the threshold frequency when the brake pedal is detected to be operated or the detected throttle valve opening speed is greater than a reference opening speed.
Claim 8
Dependent Claim
74 words
The electronic controlled fluid suspension system according to claim 5, wherein: the electronic controlled fluid suspension system further comprises a longitudinal acceleration detection means for detecting said longitudinal acceleration of the body; and the target determination means comprises a means for determining the target pitch signal according to the detected longitudinal acceleration, and a means for setting the target pitch signal at zero when the detected longitudinal acceleration is greater than a predetermined value.
References Cited (Backward Citations)
JPS57126705A
Cited
WO1984002886A1
Cited
JPS60500662A
Cited
US4770438A
Cited
JPS61193907A
Cited
US4749210A
Cited
US4765649A
Cited
US4787649A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |