Claims
- 1. A road surface friction sensor comprising two sets of two strain gauges, the strain gauges of each of the sets intersecting each other on a structure of a vehicle in the vicinity of a wheel of the vehicle, the four strain gauges constituting a bridge circuit for detecting a shear strain occurring on said structure, detection signals being outputted from said bridge circuit proportional to road surface frictional force.
- 2. A road surface friction sensor according to claim 1 wherein said structure is an axle housing.
- 3. A road surface friction coefficient detector consisting essentially of a road surface friction sensor and a vertical load sensor, each of said sensors comprising two sets of two strain gauges, the strain gauges of each of the sets intersecting each other on a structure of a vehicle in the vicinity of a wheel of the vehicle, the four strain gauges of each of the sensors constituting a respective one of two bridge circuits for detecting a shear strain occurring on said structure, detection signals being outputted from one of said bridge circuits proportional to road surface frictional force and from the other of said bridge circuits proportional to vertical load, and means for calculating the quotient of road surface frictional force and vertical load and outputting a signal proportional to the road surface friction coefficient.
- 4. A road surface friction coefficient detector according to claim 3 wherein said structure is an axle housing.
Priority Claims (4)
Number |
Date |
Country |
Kind |
63-259224 |
Oct 1988 |
JPX |
|
63-259225 |
Oct 1988 |
JPX |
|
63-259226 |
Oct 1988 |
JPX |
|
1-44537 |
Feb 1989 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 08/731,101, filed Oct. 9, 1996, now abandoned, which is a continuation of application Ser. No. 08/512,051, filed Aug. 7, 1995, now abandoned, which is a continuation of application Ser. No. 08/277,941, filed Jul. 20, 1994, now abandoned, which is a continuation of application Ser. No. 07/832,634, filed Feb. 7, 1992, now abandoned, which is a continuation of application Ser. No. 07/514,457, filed Apr. 25, 1990, now abandoned, which is a division of application Ser. No. 07/370,224, filed Jun. 22, 1989, now abandoned.
US Referenced Citations (13)
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DEX |
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JPX |
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JPX |
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JPX |
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GBX |
Non-Patent Literature Citations (4)
Entry |
Patent Abstracts of Japan: Grp. M074, vol. 5, No. 93; ABS pub. dat Jun. 17, 1981 (56-39946). |
"Automatic Electrical Measurement of Contact Pressure Distribution of a Spherical Wheel Running on Soft Powdery Ground"; Japanese Journal of Applied Physics; vol. 21, No. 6, pp. 940-943, Jun. 1982; in 73/146 Kiyoshi Takahashi et al. |
Patent Abstract of Japan; Grp. M 404, vol. 9, No. 198; ABS pub. date Aug. 15, 1985 (60-61354). |
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Divisions (1)
|
Number |
Date |
Country |
Parent |
370224 |
Jun 1989 |
|
Continuations (5)
|
Number |
Date |
Country |
Parent |
731101 |
Oct 1996 |
|
Parent |
512051 |
Aug 1995 |
|
Parent |
277941 |
Jul 1994 |
|
Parent |
832634 |
Feb 1992 |
|
Parent |
514457 |
Apr 1990 |
|