US3735200A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wheel slip sensor
Assignee: Unisys Corp
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Filing: 1971-12-08
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Granted: 1973-05-22
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Expires: 1991-12-08
Abstract
Abstract Slippage of a drive wheel in a land vehicle is detected by means of doppler shifts induced in pulsed ultrasonic beams. First and second transducers transmit bursts of ultrasonic energy which are directed at the wheel surface and the ground surface, respectively. The doppler shifted return pulses are detected by respective transducers and processed in separate channels. Counters in each channel generate gate signals indicative of the length of time that is required for the corresponding transducer to receive a predetermined number of cycles of reflected energy. An up-down counter operates from a high frequency clock in response to the two gate signals. The difference in duration of the two gate signals leaves a differential count accumulated in the up-down counter which represents the slip between wheel and ground surfaces.
Inventors
- 👤 J Kritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:17
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/171; B60T8/172; G; G01; G01P; G01P3/00; G01P3/42; G01P3/56; G01P3/60; G01S; G01S15/00; G01S15/02; G01S15/50; G01S15/58; G01S15/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
174 words
A wheel slip sensor for a land vehicle propelled by a driver wheel comprising first and second acoustic transducers disposed to irradiate a surface of said wheel and the surface being traversed by said vehicle respectively, means for periodically energizing both of said transducers so as to produce simultaneous bursts of oscillatory acoustic energy, said transducers being further responsive to energy reflected from the respective surfaces so as to produce oscillatory electrical signals corresponding to the received acoustic energy, first and second receive channels for processing the electrical signals produced by said first and second transducers respectively, means to actuate both of said receive channels at a predetermined time after the termination of each burst of transmitted energy, means in each receive channel for producing an enabling pulse having a duration that is a function of the frequency of the oscillatory signal in that channel, means to determine the difference in duration of the enabling pulses in the two receive channels, and means to produce output signals representative of said difference in pulse duration.
Claim 2
Dependent Claim
174 words
A wheel slip sensor for a land vehicle propelled by a driver wheel comprising first and second acoustic transducers disposed to irradiate a surface of said wheel and the surface being traversed by said vehicle respectively, means for periodically energizing both of said transducers so as to produce simultaneous bursts of oscillatory acoustic energy, said transducers being further responsive to energy reflected from the respective surfaces so as to produce oscillatory electrical signals corresponding to the received acoustic energy, first and second receive channels for processing the electrical signals produced by said first and second transducers respectively, means to actuate both of said receive channels at a predetermined time after the termination of each burst of transmitted energy, means in each receive channel for producing an enabling pulse having a duration that is a function of the frequency of the oscillatory signal in that channel, means to determine the difference in duration of the enabling pulses in the two receive channels, and means to produce output signals representative of said difference in pulse duration.
Claim 3
Dependent Claim
109 words
The sensor of claim 1 in which the enabling pulse producing means in each receive channel includes a predetermined counter, a flip-flop, means for simultaneously resetting the predetermined counters in both channels, and means for setting a flip-flop into a first stable state in response to an input signal applied to the predetermined counter in the same channel, each of said pRedetermined counters being arranged to reset the flip-flop in the same channel to a second stable state when the counter reaches the predetermined condition, each flip-flop having a direct output terminal for providing an enabling pulse during the time that the flip-flop is in said first stable state.
Claim 4
Dependent Claim
102 words
The sensor of claim 2 in which each of said counters is set to reach the predetermined condition after accumulating the same number of counts and in which each flip-flop further contains a complementary output terminal connected to be energized when the flip-flop is in said second stable state, said means for determining the differential in enabling pulse duration including an AND gate in each receive channel, each of said AND gates being responsive to the enabling pulse from the flip-flop in that channel and to a voltage appearing on the complementary output terminal of the flip-flop in the opposite receive channel.
Claim 5
Dependent Claim
48 words
The sensor of claim 3 further including an up-down counter arranged to be actuated in the ''''up'''' mode in response to an output signal from one of said AND gates and in the ''''down'''' mode in response to an output signal from the other of said AND gates.
Claim 6
Dependent Claim
68 words
The sensor of claim 4 further including a source of clock pulses and means to apply said clock pulses to the inputs of each of said AND gates, whereby either AND gate passes a train of clock pulses when and only when the flip-flop in the corresponding receive channel is in said first stable state and the flip-flop in the opposite channel is in said second binary state.
Claim 7
Dependent Claim
24 words
The sensor of claim 5 in which the up-down counter is arranged to count the number of clock pulses produced by said AND gates.
Claim 8
Dependent Claim
41 words
The sensor of claim 6 further including means to produce a first output signal indicative of the number of pulses accumulated by said up-down counter and a second output signal indicative of the mode in which the accumulated count is changing.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |