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US5307293A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for measuring speed

Assignee: ZF International UK Ltd
•
Filing: 1992-05-12
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Granted: 1994-04-26
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Expires: 2012-05-12
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Abstract

Abstract An apparatus for measuring speed with respect to an object comprises first to Nth sensors sensitive to energy received from first to Nth consecutive regions, respectively, of the object. Signal delay means are provided to delay the signals from the second to Nth sensors, the delay increasing with sensor number. A subtractor is provided to form the difference between the sum of the signals of the even-numbered sensors and the sum of the signals of the odd-numbered sensors.

Inventors

  • 👤 Izumi Sakai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 12:13
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/50; G01S13/58; G01S13/60; G01S13/605; G01P; G01P3/00; G01P3/36; G01S17/00; G01S17/02; G01S17/50; G01S17/58; G01S7/00; G01S7/48; G01S7/491; G01S7/4912

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 126 words
An apparatus for measuring speed with respect to an object, comprising first and Nth sensors where N is greater than two arranged to be sensitive to energy received from first to Nth consecutive regions, respectively, of the object to form sensor signals, signal delay means for forming delayed signal by delaying the sensor signals from at least said second to Nth sensors such that a time delay for each ith of the sensor signal is greater than a time delay for each (i-1)th of the sensor signals for 1<i≦N, and first difference forming means for forming a difference between a sum of the delayed signals of ever numbered ones of said sensors and a sum of the delayed signals of odd numbered ones of said sensors.
Claim 2
Independent Claim 126 words
An apparatus for measuring speed with respect to an object, comprising first and Nth sensors where N is greater than two arranged to be sensitive to energy received from first to Nth consecutive regions, respectively, of the object to form sensor signals, signal delay means for forming delayed signal by delaying the sensor signals from at least said second to Nth sensors such that a time delay for each ith of the sensor signal is greater than a time delay for each (i-1)th of the sensor signals for 1<i≦N, and first difference forming means for forming a difference between a sum of the delayed signals of ever numbered ones of said sensors and a sum of the delayed signals of odd numbered ones of said sensors.
Claim 3
Dependent Claim 14 words
An apparatus as claimed in claim 1, in which N is an even integer.
Claim 4
Dependent Claim 34 words
An apparatus as claimed in claim 2, in which said signal delay means are arranged to provide time delays of the sensor signals from the second to Nth sensors which increase in arithmetic progression.
Claim 5
Dependent Claim 34 words
An apparatus as claimed in claim 1, further comprising a band-pass filter having an input and an output, said first difference forming means having an output connected to said input of said band-pass filter.
Claim 6
Dependent Claim 32 words
An apparatus as claimed in claim 4, further comprising a comparator having a signal input and an output, said input of said comparator being connected to said output of said band-pass filter.
Claim 7
Dependent Claim 16 words
An apparatus as claimed in claim 5, in which said comparator is a zero crossing detector.
Claim 8
Dependent Claim 26 words
An apparatus as claimed in claim 1, further comprising a frequency measuring device for measuring the frequency of the output of said first difference forming means.
Claim 9
Dependent Claim 71 words
An apparatus as claimed in claim 5, further comprising a frequency measuring device for measuring the frequency of the output of said comparator and a look-up table having an address input and an output, said frequency measuring device having an output connected to said address input of said look-up table, and said look-up table being arranged to provide an output signal at said output which is substantially linearly related to speed.
Claim 10
Dependent Claim 72 words
An apparatus as claimed in claim 1, further comprising second difference forming means for forming a difference between a sum of the sensor signals of even-numbered ones of said sensors and a sum of the sensor signals of odd-numbered ones of said sensors, and frequency comparing means for comparing the frequencies of the differences formed by said first difference forming means and said second difference forming means to generate a direction signal.
Claim 11
Dependent Claim 67 words
An apparatus as claimed in claim 9, further comprising first and second look-up tables having respective address inputs and respective outputs, a frequency measuring device having an input connected to said first difference forming means and an output connected to said respective address inputs of said first and second look-up tables, and means responsive to the direction signal for selecting between said first and second look-up tables.
Claim 12
Dependent Claim 35 words
An apparatus as claimed in claim 10, in which said first and second look-up tables are arranged to produce signals at said respective outputs substantially linearly related to speed in first and second directions, respectively.
Claim 13
Dependent Claim 72 words
An apparatus as claimed in claim 1, further comprising second difference forming means for forming a difference between a sum of the sensor signals of even-numbered ones of said sensors and a sum of the sensor signals of odd-numbered ones of said sensors, and phase comparing means for comparing the phases of the differences formed by said first difference forming means and said second difference forming means to generate a direction signal.
Claim 14
Dependent Claim 67 words
An apparatus as claimed in claim 12, further comprising first and second look-up tables having respective address inputs and respective outputs, a frequency measuring device having an input connected to said first difference forming means and an output connected to said respective address inputs of said first and second look-up tables, and means responsive to the direction signal for selecting between said first and second look-up tables.
Claim 15
Dependent Claim 35 words
An apparatus as claimed in claim 13, in which said first and second look-up tables are arranged to produce signals at said respective outputs substantially linearly related to speed in first and second directions, respectively.
Claim 16
Dependent Claim 14 words
An apparatus as claimed in claim 1, in which said sensors are optical sensors.
Claim 17
Dependent Claim 14 words
An apparatus as claimed in claim 1, in which said sensors are ultrasonic sensors.
Claim 18
Dependent Claim 22 words
An apparatus as claimed in claim 1, in which said sensors are arranged in a linear array for measuring linear relative movement.
Claim 19
Dependent Claim 24 words
An apparatus as claimed in claim 1, in which said sensors are arranged in a curved one dimensional array for measuring relative rotary movement.
Claim 20
Dependent Claim 13 words
A vehicle speed measuring apparatus including an apparatus as claimed in claim 1.

References Cited (Backward Citations)

US4282511A Cited
US4659937A Cited
US4923298A Cited
US4927263A Cited
US5172000A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-04-25 1997-10-25 1998-04-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-04-25 2001-10-25 2002-04-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-04-25 2005-10-25 2006-04-26 $7700.00 Window Closed / Lapsed

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