Patent US3757167A successfully refreshed from Google Patents.
US3757167A
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US
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Revolutions measuring instrument
Assignee: Toyota Motor Corp
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Filing: 1972-03-24
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Granted: 1973-09-04
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Expires: 1992-03-24
Abstract
Abstract An instrument for measuring the revolutions of a rotary body comprising a speed pulse generator for generating a first train of pulses including, in a unit length of time, pulses of the number proportional to the revolutions of the rotary body, a reference pulse generator for generating a second train of pulses including a certain number of pulses in a unit time, and first and second counters for counting the number of pulses appearing in the first and second pulse trains respectively during a counting cycle starting with a certain pulse in the first pulse train; wherein the counting operations of both the counters are stopped simultaneously with the appearance of the first pulse of the first pulse train immediately following the time at which the second counter has counted a predetermined number of pulses, and the number counted by the first counter is divided by the number counted by the second counter, thereby measuring the revolutions of the rotary body.
Inventors
- 👤 I Yoshikawa
- 👤 T Ochiai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:11
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/172; G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/481; G01P3/489; G01P3/56; G01P3/60
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
226 words
A system for measuring the revolutions of a rotary body comprising: a speed pulse generating means for generating a first pulse train containing in a unit length of time pulses of the number proportional to the revolutions of said rotary body, a reference pulse generating means for generating a second pulse train containing a certain number of pulses in a unit length of time, a first counter for counting and storing the information on the number of pulses in said first pulse train, a second counter for counting and storing the information on the number of pulses in said second pulse train, a control means for controlling the period of one counting cycle and causing the first and second counters to count pulses occurring in the first and second pulse trains respectively during said cycle, said counting cycle starting with the appearance of a certain pulse in the first pulse train and ending with the appearance of the first pulse of the first pulse train immediately following the time point at which time the second counter has counted a predetermined number of pulses, and a dividing means for dividing the number counted by the first counter during said counting cycle and stored in said first counter by the number counted by and stored in the second counter, thereby to calculate the revolutions of said rotary body.
Claim 2
Independent Claim
226 words
A system for measuring the revolutions of a rotary body comprising: a speed pulse generating means for generating a first pulse train containing in a unit length of time pulses of the number proportional to the revolutions of said rotary body, a reference pulse generating means for generating a second pulse train containing a certain number of pulses in a unit length of time, a first counter for counting and storing the information on the number of pulses in said first pulse train, a second counter for counting and storing the information on the number of pulses in said second pulse train, a control means for controlling the period of one counting cycle and causing the first and second counters to count pulses occurring in the first and second pulse trains respectively during said cycle, said counting cycle starting with the appearance of a certain pulse in the first pulse train and ending with the appearance of the first pulse of the first pulse train immediately following the time point at which time the second counter has counted a predetermined number of pulses, and a dividing means for dividing the number counted by the first counter during said counting cycle and stored in said first counter by the number counted by and stored in the second counter, thereby to calculate the revolutions of said rotary body.
Claim 3
Dependent Claim
218 words
A revolutions measuring system according to claim 1, wherein said second counter produces a signal when the number counted by said second counter reaches a predetermined value, and said control means comprises a first gate connected between said speed pulse generator and said first counter for alternating between the opened state where said first pulse train is allowed to pass to said first counter and the closed state where said first train is prevented from being applied to said first counter, a second gate connected between said reference pulse generator and said second counter for alternating between the opened state where said second pulse train is allowed to pass to said second counter and the closed state where said second pulse train is prevented from being applied to said second counter, and a flip-flop circuit for controlling said first and second gates, said flip-flop circuit applying to each gate a first gate that is the signal of the first pulse train first appearing in the absence of any signal in said second counter, said first signal opening said each gate, said flip-flop circuit also applying to each gate a second signal that is the signal of the first pulse train appearing in the presence of a signal in said second counter, said second signal closing said each gate.
Claim 4
Dependent Claim
133 words
A revolutions measuring system according to claim 2, further comprisiNg a third counter for generating a control pulse train in synchronism with the second pulse train received from said reference pulse generating means, and a third gate inserted between said third counter and said reference pulse generating means for alternating between the opened state where said second pulse train is allowed to pass to said third counter and the closed state where said second pulse train is prevented from being applied to said third counter, said flip-flop circuit producing a third signal simultaneously with said second signal, said third signal being applied to said third gate to open the same, said dividing means being adapted to read out the information stored in said first and second counters in response to said control pulse.
Claim 5
Dependent Claim
60 words
A revolutions measuring system according to claim 2, in which each of said first and second counters comprises a feedback circuit for generating a signal which is applied to said first and second gates respectively thereby preventing a pulse from being applied to said each of the counters when said each counter has completed the counting of a predetermined number.
Claim 6
Dependent Claim
58 words
A revolutions measuring system according to claim 1, wherein a vehicle wheel speed is to be measured for determining the speed of a vehicle therefor and in which said rotary body rotates with revolutions proportional to the vehicle wheel speed, and the rotational speed obtained by said dividing means is used to control a drive of said vehicle.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |