Patent US5386727A successfully refreshed from Google Patents.
US5386727A
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Dynamic rail longitudinal stress measuring system
Assignee: Herzog Contracting Corp
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Filing: 1993-03-03
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Granted: 1995-02-07
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Expires: 2013-03-03
Abstract
Abstract A system and method for dynamically and non-destructively measuring the longitudinal stresses in a rail of a continuous rail track includes an ultrasonic transmitter which transmits a signature coded pulse pattern through a rail which pulse pattern is altered by the rail section dependent upon the longitudinal stress within the rail. The altered pulse pattern is then received and a data processor, in conjunction with a rail height detector, a rail temperature detector, and a rail splice detector, dynamically determines the longitudinal stresses in the rail as a function of the received pulse characteristics and calculates the stress free temperature (SFT) of the rail. A rail marker marks portions of the rail having unacceptable SFT values. Stress and related rail data are recorded on a data log. A position sensor provides milepost positions to three decimal places.
Inventors
- 👤 Donald S. Searle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:18
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/04; G01N29/043; G01L; G01L1/00; G01L1/25; G01L1/255; G01N29/06; G01N29/0609; G01N29/0618; G01N29/07; G01N29/11; G01N29/22; G01N29/24; G01N29/2412; G01N29/2468; G01N29/2493; G01N29/30; G01N29/32; G01N29/326; G01N29/44; G01N29/46; G01N2291/00; G01N2291/02; G01N2291/028; G01N2291/02827; G01N2291/02854; G01N2291/04; G01N2291/042; G01N2291/0422; G01N2291/044; G01N2291/10; G01N2291/103; G01N2291/26; G01N2291/262; G01N2291/2623
Claims Analysis
Total Claims: 46
Claim 1
Independent Claim
107 words
An apparatus for measuring the longitudinal stress in a section of railroad rail, comprising: (a) transmitting means for transmitting an ultrasonic signature signal into said section of rail; (b) receiving means spaced from said transmitting means for receiving the transmitted ultrasonic signature signal from said section of rail, said received signature signal having been altered by said rail section depending upon the longitudinal stress within said rail section; (c) means for processing the altered ultrasonic signature signal to generate a variable dependent upon the longitudinal stress in said rail section; and (d) means for calculating the longitudinal stress in the rail section based upon said generated variable.
Claim 2
Independent Claim
107 words
An apparatus for measuring the longitudinal stress in a section of railroad rail, comprising: (a) transmitting means for transmitting an ultrasonic signature signal into said section of rail; (b) receiving means spaced from said transmitting means for receiving the transmitted ultrasonic signature signal from said section of rail, said received signature signal having been altered by said rail section depending upon the longitudinal stress within said rail section; (c) means for processing the altered ultrasonic signature signal to generate a variable dependent upon the longitudinal stress in said rail section; and (d) means for calculating the longitudinal stress in the rail section based upon said generated variable.
Claim 3
Dependent Claim
40 words
An apparatus as in claim 1, and further including: (a) a vehicle for moving said apparatus along said rail, said apparatus making repeated measurements of longitudinal stress at different testing points within each of multiple rail sections of said rail.
Claim 4
Dependent Claim
21 words
An apparatus as in claim 2, and further including: (a) a rail temperature detector for detecting the temperature of said rail.
Claim 5
Dependent Claim
16 words
An apparatus as in claim 3, wherein: (a) said rail temperature detector utilizes infrared measuring techniques.
Claim 6
Dependent Claim
22 words
An apparatus as in claim 3, and further including: (a) a rail height detector for continuously determining the height of said rail.
Claim 7
Dependent Claim
18 words
An apparatus as in claim 5, wherein: (a) said rail height detector includes an ultrasonic transmitter and detector.
Claim 8
Dependent Claim
25 words
An apparatus as in claim 5, and further including: (a) a rail position detector for continuously determining the position of said apparatus along said rail.
Claim 9
Dependent Claim
28 words
An apparatus as in claim 7, wherein: (a) said calculating means further includes means for calculating the stress free temperature of said rail section at each testing point.
Claim 10
Dependent Claim
28 words
An apparatus as in claim 8, and further comprising: (a) means for maintaining a continuous log of rail conditions as said apparatus is moved along said rail section.
Claim 11
Dependent Claim
46 words
An apparatus as in claim 9, wherein: (a) said log includes one or more of the following: (i) longitudinal rail stress; (ii) rail stress free temperature; (iii) rail temperature; (iv) rail height; (v) rail position; and (vi) rail events such as crossings, curves, rail boundaries, etc.
Claim 12
Dependent Claim
58 words
An apparatus as in claim 2, wherein: (a) said transmitting means transmits a series of ultrasonic signature signals, each ultrasonic signature signal being composed of a plurality of ultrasonic pulses; and (b) said processing means generates said variable from a measured differential pulse transit time between selected pulses of at least two different signature signals in said series.
Claim 13
Dependent Claim
24 words
An apparatus as in claim 11, wherein: (a) said receiving means comprises at least one sensor spaced from said transmitting means along said rail.
Claim 14
Dependent Claim
22 words
An apparatus as in claim 12, wherein: (a) the spacing of said at least one sensor from said transmitting means is variable.
Claim 15
Dependent Claim
25 words
An apparatus as in claim 12, wherein: (a) said receiving means comprises noise suppression means for suppressing extraneous signals not related to said signature series.
Claim 16
Dependent Claim
57 words
An apparatus as in claim 12, wherein said transmitting means comprises: (a) an ultrasonic generator means; and (b) a wheel containing said generator means, said wheel being in contact with said rail and being filled with a fluid adapted to provide a reliable conduction medium for said ultrasonic signals from said generator means into said rail section.
Claim 17
Dependent Claim
48 words
An apparatus as in claim 1, wherein: (a) said transmitting means and said receiving means are contained at either end of an elongate portable, hand-held frame; and (b) said frame is adjustable lengthwise such that the spacing between said transmitting means and said receiving means can be varied.
Claim 18
Dependent Claim
21 words
An apparatus as in claim 16, wherein: (a) said hand-held frame comprises means for attaching said apparatus to said rail section.
Claim 19
Dependent Claim
28 words
An apparatus as in claim 17, wherein: (a) said means for attaching said apparatus to said rail section includes a surface which can be selectively magnetized and demagnetized.
Claim 20
Dependent Claim
16 words
An apparatus as in claim 16, wherein: (a) said apparatus further includes a rail temperature sensor.
Claim 21
Dependent Claim
26 words
An apparatus as in claim 16, wherein: (a) said processing means and said calculating means are removably attachable to said transmitting means and said receiving means.
Claim 22
Dependent Claim
59 words
An apparatus as in claim 16, wherein: (a) said transmitting means transmits a series of ultrasonic signature signals, each signature signal being composed of a plurality of ultrasonic pulses; and (b) said processing means generates said variable from the differential transit time between selected pulses of at least two different signals of said series which reaches said receiving means.
Claim 23
Dependent Claim
38 words
An apparatus as in claim 16, wherein: (a) said transmitting means transmits a series of signature pulses into said rail section; and (b) said processing means generates said variable from the number of pulses reaching said receiving means.
Claim 24
Dependent Claim
42 words
An apparatus as in claim 16, wherein: (a) said transmitting means transmits a series of ultrasonic waves into said rail; and (b) said processing means generates said variable from the amplitude of one or more of the waves reaching said receiving means.
Claim 25
Independent Claim
155 words
An apparatus for dynamically measuring the longitudinal stress in a section of railroad rail, comprising: (a) transmitting means for transmitting a series of ultrasonic signature signals into said section of rail; (b) receiving means spaced from said transmitting means for receiving the transmitted ultrasonic signature signals from said section of rail, said received signature signals having been altered by said rail section depending upon the longitudinal stress within said rail section; (c) means for processing the received, altered ultrasonic signature signals to generate a variable dependent upon the longitudinal stress in said rail section, said variable being determined from said alteration of said signature signals; (d) means for calculating the longitudinal stress in the tested rail section based upon said generated variable; and (e) a vehicle for moving said apparatus along said rail, said apparatus making repeated measurements of longitudinal stress within each section of said railroad rail as said vehicle moves along the rail.
Claim 26
Independent Claim
155 words
An apparatus for dynamically measuring the longitudinal stress in a section of railroad rail, comprising: (a) transmitting means for transmitting a series of ultrasonic signature signals into said section of rail; (b) receiving means spaced from said transmitting means for receiving the transmitted ultrasonic signature signals from said section of rail, said received signature signals having been altered by said rail section depending upon the longitudinal stress within said rail section; (c) means for processing the received, altered ultrasonic signature signals to generate a variable dependent upon the longitudinal stress in said rail section, said variable being determined from said alteration of said signature signals; (d) means for calculating the longitudinal stress in the tested rail section based upon said generated variable; and (e) a vehicle for moving said apparatus along said rail, said apparatus making repeated measurements of longitudinal stress within each section of said railroad rail as said vehicle moves along the rail.
Claim 27
Dependent Claim
21 words
An apparatus as in claim 24, and further including: (a) a rail temperature detector for detecting the temperature of said rail.
Claim 28
Dependent Claim
22 words
An apparatus as in claim 25, and further including: (a) a rail height detector for continuously determining the height of said rail.
Claim 29
Dependent Claim
25 words
An apparatus as in claim 26, and further including: (a) a rail position detector for continuously determining the position of said apparatus along said rail.
Claim 30
Dependent Claim
27 words
An apparatus as in claim 27, and further including: (a) means for maintaining a continuous log of rail conditions as said apparatus is moved along said rail.
Claim 31
Dependent Claim
46 words
An apparatus as in claim 28, wherein: (a) said log includes one or more of the following: (i) longitudinal rail stress; (ii) rail stress free temperature; (iii) rail temperature; (iv) rail height; (v) rail position; and (vi) rail events such as crossings, curves, rail boundaries, etc.
Claim 32
Dependent Claim
20 words
An apparatus as in claim 24, wherein: (a) the spacing of said receiving means from said transmitting means is variable.
Claim 33
Dependent Claim
25 words
An apparatus as in claim 24, wherein: (a) said receiving means comprises noise suppression means for suppressing extraneous signals not related to said signature series.
Claim 34
Dependent Claim
50 words
An apparatus as in claim 24, wherein: (a) each of said ultrasonic signature signals is composed of a plurality of ultrasonic pulses; and (b) said processing means generates said variable from a measured differential pulse transit time between selected pulses of at least two different signature signals in said series.
Claim 35
Dependent Claim
39 words
An apparatus as in claim 24, wherein: (a) each of said ultrasonic signature signals is composed of a plurality of ultrasonic pulses; and (b) said processing means generates said variable from the number of pulses reaching said receiving means.
Claim 36
Dependent Claim
44 words
An apparatus as in claim 24, wherein: (a) each of said ultrasonic signature signals is composed of at least one ultrasonic wave; and (b) said processing means generates said variable from the amplitude of one or more of the waves reaching said receiving means.
Claim 37
Independent Claim
107 words
A method of determining the longitudinal stress in a section of railroad rail, comprising the steps of: (a) transmitting a series of ultrasonic signature signals into said rail at a point in said rail section; (b) receiving said ultrasonic signature signals from said rail at another point in said rail section, said received signature signals having been altered by said rail section depending upon the longitudinal stress within said rail section; (c) processing said received altered signals to yield a variable dependent upon the alteration of said signature signals by said longitudinal stress within said rail section; and (d) calculating said longitudinal stress based upon said variable.
Claim 38
Independent Claim
107 words
A method of determining the longitudinal stress in a section of railroad rail, comprising the steps of: (a) transmitting a series of ultrasonic signature signals into said rail at a point in said rail section; (b) receiving said ultrasonic signature signals from said rail at another point in said rail section, said received signature signals having been altered by said rail section depending upon the longitudinal stress within said rail section; (c) processing said received altered signals to yield a variable dependent upon the alteration of said signature signals by said longitudinal stress within said rail section; and (d) calculating said longitudinal stress based upon said variable.
Claim 39
Dependent Claim
52 words
A method as in claim 35, and further comprising the steps of: (a) detecting the temperature within said rail section; (b) detecting the rail height of said rail section; and (c) using said rail temperature, said rail height and said calculated stress to calculate the stress free temperature of said rail section.
Claim 40
Dependent Claim
52 words
A method as in claim 35, and further comprising the steps of: (a) repeatedly transmitting and receiving said signals while moving said points at which said signature signal series transmitted and received; whereby (b) said longitudinal stress and said stressfree temperature are repeatedly calculated for the entire length of said rail section.
Claim 41
Dependent Claim
27 words
A method as in claim 37, and further comprising the step of: (a) maintaining a log of rail conditions as said transmitting and receiving points are moved.
Claim 42
Dependent Claim
41 words
A method as in claim 36, and further comprising the steps of: (a) using said rail height to adjust the distance between the point at which said signature series signal is transmitted and the point at which said series is received.
Claim 43
Dependent Claim
47 words
A method as in claim 35, wherein: (a) each of said ultrasonic signature signals comprises a plurality of ultrasonic pulses: and (b) said variable is generated from a measured differential pulse transit time between selected pulses of at least two different ultrasonic signature signals in said series.
Claim 44
Dependent Claim
32 words
A method as in claim 35, wherein: (a) each of said ultrasonic signature signals comprises a plurality of ultrasonic pulses; and (b) said variable is generated from the number of received pulses.
Claim 45
Dependent Claim
37 words
A method as in claim 35, wherein: (a) each of said ultrasonic signature signals comprises a plurality of ultrasonic waves; and (b) said variable is generated from the amplitude of one or more of the received waves.
Claim 46
Dependent Claim
31 words
A method as in claim 35, and further comprising: (a) initially transmitting and receiving said series along a length of stress free rail to provide a base value for said variable.
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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) | 1998-02-06 | 1998-08-08 | 1999-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-02-06 | 2002-08-08 | 2003-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-02-06 | 2006-08-08 | 2007-02-07 | $7700.00 | Window Closed / Lapsed |