US3642329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wheel slip detection device particularly for multiwheel vehicles
Assignee: Robert Bosch GmbH
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Filing: 1970-04-20
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Granted: 1972-02-15
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Expires: 1990-04-20
Abstract
Abstract To detect transition from rolling to slipping of a wheel over a surface, a transducer coupled to the wheel provides output pulses having a repetition rate representative of wheel speed. The pulses are applied to a logic circuit, including a pair of multivibrators, one of which has a variable time circuit, controlling its unstable state in dependence on pulse repetition rate. Control of the unstable state is obtained by means of a band-pass filter coupled to an integrator, the output of the band-pass filter further controlling a comparison and coincidence network, the output from the network activating a wheel slip detector and, if desired, overriding control of braking.
Inventors
- 👤 Richard Zechnall
- 👤 Helmut Domann
- 👤 Helmut Fleischer
- 👤 Klaus Christ
- 👤 Wolfgang Maisch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:57
CPC Classifications
G; G01; G01P; G01P3/00; G01P3/42; G01P3/50; B; B60; B60T; B60T8/00; B60T8/17; B60T8/172; B60T8/32; B60T8/321; B60T8/329; G01P3/44; G01P3/48; G01P3/4802
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
227 words
Wheel slip detection device to detect transition from rolling to sliding of a wheel (11) over a surface (12) upon change of speed of the wheel comprising transducer means (18) coupled to the wheel and providing an output signal (118) having a characteristic representative of wheel speed; means (34, 35) connected to said transducer means and deriving a pulse sequence having a distance between pulses representative of wheel speed; circuit means (36, 38) including an integrating network, said circuit means being connected to have the pulses of said pulse sequence applied thereto and sensing change of elapsed time between said pulses; means (42, 43) sensing excess change in the rate of change of pulses beyond a predetermined limit; and means (47, 46) deriving an output signal from said sensing means, wherein said means deriving the pulse sequence includes a wave shaping network (34); and said circuit means includes an input monostable multivibrator (36) connected to said pulse shaping network and changing state upon occurrence of each pulse from said wave shaping network; and a low-pass filter (37) interconnecting the output of said monostable multivibrator (36) and said integrating network (38), the output of said integrating network being connected back to said monostable multivibrator to control the unstable time period thereof in accordance with the rate of pulses applied to said integrating network through said low-pass filter (37).
Claim 2
Dependent Claim
227 words
Wheel slip detection device to detect transition from rolling to sliding of a wheel (11) over a surface (12) upon change of speed of the wheel comprising transducer means (18) coupled to the wheel and providing an output signal (118) having a characteristic representative of wheel speed; means (34, 35) connected to said transducer means and deriving a pulse sequence having a distance between pulses representative of wheel speed; circuit means (36, 38) including an integrating network, said circuit means being connected to have the pulses of said pulse sequence applied thereto and sensing change of elapsed time between said pulses; means (42, 43) sensing excess change in the rate of change of pulses beyond a predetermined limit; and means (47, 46) deriving an output signal from said sensing means, wherein said means deriving the pulse sequence includes a wave shaping network (34); and said circuit means includes an input monostable multivibrator (36) connected to said pulse shaping network and changing state upon occurrence of each pulse from said wave shaping network; and a low-pass filter (37) interconnecting the output of said monostable multivibrator (36) and said integrating network (38), the output of said integrating network being connected back to said monostable multivibrator to control the unstable time period thereof in accordance with the rate of pulses applied to said integrating network through said low-pass filter (37).
Claim 3
Dependent Claim
43 words
Device according to claim 1 wherein said means sensing excess change in the rate of change of pulses includes a hysteresis circuit (42) connecTed to the low-pass filter (37) to sense deviation of output voltage of the low-pass filter from a predetermined value.
Claim 4
Dependent Claim
13 words
Device according to claim 2 wherein the hysteresis circuit is an operational amplifier.
Claim 5
Dependent Claim
13 words
Device according to claim 2 wherein the hysteresis circuit is a Schmitt trigger.
Claim 6
Dependent Claim
61 words
Device according to claim 1 including means (48, 51, 52, 45) sensing low absolute speed of the wheel below a predetermined limit; said means deriving an output signal including a coincidence network (44) having an output from said sensing circuit (42, 43) applied to one input thereof and the output from said low absolute speed sensing means to another input thereof.
Claim 7
Dependent Claim
49 words
Device according to claim 5 sensing wheel slip for a plurality of wheels, each provided with a transducer, wherein said low absolute speed sensing means comprises an AND-gate (51) having one input each connected to a transducer (18) and delivering said signals having said characteristics representative of wheel speed.
Claim 8
Dependent Claim
81 words
Device according to claim 6 wherein said means sensing excess change of rate of pulses includes a hysteresis circuit (42) connected to the low-pass filter (37) and an output monostable multivibrator (43) having its input connected to said hysteresis circuit; the output of said monostable multivibrator (43) being connected to said AND gate (51) and to said means delivering an output signal, said AND gate (51) being enabled when the speed of the wheels is in excess of said predetermined limit.
Claim 9
Dependent Claim
32 words
Device according to claim 1 wherein said means deriving a pulse sequence comprises a Schmitt trigger circuit (34) and a differentiating network (35) connected to the output of said Schmitt trigger circuit.
Claim 10
Dependent Claim
113 words
Multiple wheel vehicle having a wheel slip detection device in accordance with claim 1, wherein each wheel, or group of wheels is associated with: a transducer means (18); means delivering a pulse sequence (34, 35); and circuit means sensing change of elapsed time between pulses (36, 38); means sensing excess change in the rate of change of pulses (42, 43); and means (47, 46) deriving an output signal from said sensing means; and wherein a common means (48, 48''); (51, 52); (45-45'') is provided sensing absolute wheel speed of all said wheels and inhibiting generation of an output signal if the speed instantaneous absolute speed of the vehicle is below a predetermined limit.
Claim 11
Dependent Claim
63 words
Device according to claim 1 wherein said transducer means includes a magnetic transducer wheel mechanically coupled to said wheel, said transducer wheel having intermittently magnetic material located along its circumference; and a yoke (28) cooperating with said intermittent magnetic material, and a coil (29) associated therewith, said coil having pulses induced therein upon rotation of said transducer wheel with respect to said yoke.
Claim 12
Dependent Claim
33 words
Device according to claim 10 wherein said transducer wheel comprises a plurality of magnets located at the circumference thereof, and of adjacent opposite polarity, and located in a magnetic circuit with said yoke.
Claim 13
Dependent Claim
29 words
Device according to claim 10 wherein said transducer wheel comprises a plurality of salient poles of ferromagnetic material and said coil is connected to a source of direct current.
Claim 14
Dependent Claim
13 words
Device according to claim 1 wherein said transducer means comprises a tachometer generator.
Claim 15
Dependent Claim
49 words
Device according to claim 1 wherein said transducer means includes an optical transducer having a source of light and the light-sensitive element, and a moveable reflector secured to rotate with said wheel (11) and reflecting light from said source to said photosensitive element, intermittently, upon rotation of said wheel.
Claim 16
Dependent Claim
47 words
Device according to claim 1 in combination with a vehicle braking system, said means (46) deriving an output signal being conNected to the vehicle braking system and supplying a control signal thereto upon detection of change of elapsed time between pulses in excess of a predetermined value.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-14 | 1975-08-16 | 1976-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-14 | 1979-08-16 | 1980-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-14 | 1983-08-16 | 1984-02-15 | $7700.00 | Window Closed / Lapsed |