US5758305A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for detecting frictional state of running road surface
Assignee: Toyota Motor Corp
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Filing: 1995-10-20
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Granted: 1998-05-26
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Expires: 2015-10-20
Abstract
Abstract In order to correctly detect the frictional state of a running road surface, the running road surface is determined as a low-friction road surface, when tire lock is detected by tire lock detection device, and besides a state in which vehicle deceleration obtained by vehicle deceleration detection means is greater than a predetermined value, is shorter than a predetermined time in a period extending from the start of braking until the tire lock.
Inventors
- 👤 Hideaki Otsubo
- 👤 Yasunori Nakawaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:33
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/172
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
152 words
A system for detecting a frictional state of a running road surface, having means for detecting vehicle deceleration from a rotational speed of a rotating member included in a power transmission path, wherein whether or not the running road surface is a low-friction road surface is detected on the basis of the vehicle deceleration during braking, comprising: a braking detector; means for detecting tire lock; means for detecting-a state in which said vehicle deceleration during braking is greater than a predetermined value, and means for determining whether said detected state lasts for shorter than a predetermined time during a period extending from start of said braking until the detection of the tire lock; and low-friction road determination means for determining said running road surface as the low-friction road surface when said tire lock is detected and said state is determined to have lasted for shorter than the predetermined time during said period.
Claim 2
Independent Claim
152 words
A system for detecting a frictional state of a running road surface, having means for detecting vehicle deceleration from a rotational speed of a rotating member included in a power transmission path, wherein whether or not the running road surface is a low-friction road surface is detected on the basis of the vehicle deceleration during braking, comprising: a braking detector; means for detecting tire lock; means for detecting-a state in which said vehicle deceleration during braking is greater than a predetermined value, and means for determining whether said detected state lasts for shorter than a predetermined time during a period extending from start of said braking until the detection of the tire lock; and low-friction road determination means for determining said running road surface as the low-friction road surface when said tire lock is detected and said state is determined to have lasted for shorter than the predetermined time during said period.
Claim 3
Independent Claim
230 words
A system for detecting a frictional state of a running road surface, having means for detecting vehicle deceleration from a rotational speed of a rotating member included in a power transmission path, wherein whether or not the running road surface is a high-friction road surface is detected on the basis of the vehicle deceleration during braking, comprising: a braking detector; means for detecting tire lock; means for detecting a first state in which said vehicle deceleration during the braking is greater than a first predetermined value, and means for determining whether said detected first state lasts for shorter than a first predetermined time during a period extending from start of said braking until the detection of the tire lock; low-friction road determination means for determining said running road surface as the low-friction road surface when said tire lock is detected said first state is determined to have lasted for shorter than the first predetermined time during said period; means for detecting a second state in which said vehicle deceleration during the braking is greater than a second predetermined value, and means for determining whether or not said detected second state continues for longer than a second predetermined time; and high-friction road determination means for determining said running road surface as the high-friction road surface when the second state is determined to have continued for longer than the second predetermined time.
Claim 4
Independent Claim
230 words
A system for detecting a frictional state of a running road surface, having means for detecting vehicle deceleration from a rotational speed of a rotating member included in a power transmission path, wherein whether or not the running road surface is a high-friction road surface is detected on the basis of the vehicle deceleration during braking, comprising: a braking detector; means for detecting tire lock; means for detecting a first state in which said vehicle deceleration during the braking is greater than a first predetermined value, and means for determining whether said detected first state lasts for shorter than a first predetermined time during a period extending from start of said braking until the detection of the tire lock; low-friction road determination means for determining said running road surface as the low-friction road surface when said tire lock is detected said first state is determined to have lasted for shorter than the first predetermined time during said period; means for detecting a second state in which said vehicle deceleration during the braking is greater than a second predetermined value, and means for determining whether or not said detected second state continues for longer than a second predetermined time; and high-friction road determination means for determining said running road surface as the high-friction road surface when the second state is determined to have continued for longer than the second predetermined time.
Claim 5
Independent Claim
274 words
A system for detecting a frictional state of a running road surface, having means for detecting vehicle deceleration from a rotational speed of a rotating member included in a power transmission path, wherein whether or not the running road surface is a low-friction road surface is detected on the basis of the vehicle deceleration during braking, comprising: a braking detector; means for detecting tire lock; means for detecting a first state in which said vehicle deceleration during the braking is greater than a first predetermined value, and means for determining whether said detected first state lasts for shorter than a first predetermined time during a period extending from start of said braking until the detection of the tire lock; low-friction road determination means for determining said running road surface as the low-friction road surface when said tire lock is detected and said first state is determined to have lasted for shorter than the first predetermined time during said period; means for detecting a second state in which said vehicle deceleration during the braking is greater than a second predetermined value, and means for determining whether or not said detected second state continues for longer than a second predetermined time; and high-friction road determination means for determining said running road surface as the high-friction road surface when the second state is determined to have continued for longer than the second predetermined time wherein; in the case where both low-friction road detecting condition and high-friction road detecting condition are not satisfied, the preceding determination of the frictional state of the running road surface is maintained as a newly determined frictional state of the running road surface.
Claim 6
Independent Claim
274 words
A system for detecting a frictional state of a running road surface, having means for detecting vehicle deceleration from a rotational speed of a rotating member included in a power transmission path, wherein whether or not the running road surface is a low-friction road surface is detected on the basis of the vehicle deceleration during braking, comprising: a braking detector; means for detecting tire lock; means for detecting a first state in which said vehicle deceleration during the braking is greater than a first predetermined value, and means for determining whether said detected first state lasts for shorter than a first predetermined time during a period extending from start of said braking until the detection of the tire lock; low-friction road determination means for determining said running road surface as the low-friction road surface when said tire lock is detected and said first state is determined to have lasted for shorter than the first predetermined time during said period; means for detecting a second state in which said vehicle deceleration during the braking is greater than a second predetermined value, and means for determining whether or not said detected second state continues for longer than a second predetermined time; and high-friction road determination means for determining said running road surface as the high-friction road surface when the second state is determined to have continued for longer than the second predetermined time wherein; in the case where both low-friction road detecting condition and high-friction road detecting condition are not satisfied, the preceding determination of the frictional state of the running road surface is maintained as a newly determined frictional state of the running road surface.
References Cited (Backward Citations)
US3861756A
Cited
US4770226A
Cited
JPH01238747A
Cited
US4936636A
Cited
US5123715A
Cited
US5092662A
Cited
US5443583A
Cited
US5257857A
Cited
US5292187A
Cited
US5444625A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-05-25 | 2001-11-24 | 2002-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-25 | 2005-11-24 | 2006-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-25 | 2009-11-24 | 2010-05-26 | $7700.00 | Window Closed / Lapsed |