US3786673A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Determination of mechanical design properties of elastic materials
Assignee: AT&T Inc
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Filing: 1972-03-15
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Granted: 1974-01-22
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Expires: 1992-03-15
Abstract
Abstract Mechanical design properties of elastic materials including design stress and design modules are determined from the energy dissipation per cycle and total elastic energy of a sample used as a spring in a one degree of freedom oscillator whose fixed end is subjected to a transient displacement during each cycle. The energy dissipation per cycle and total elastic energy are related to the steady state amplitude and frequency, respectively, of the oscillator.
Inventors
- 👤 G Weissmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 07:18
CPC Classifications
G; G01; G01N; G01N3/00; G01N2203/00; G01N2203/02; G01N2203/026; G01N2203/0288
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
118 words
An apparatus for determining the mechanical design properties of elastic materials comprising: means for supporting a sample, the means holding the sample at one end thereof, a weighted part attached to the other end of the sample, and means for producing a periodic transient displacement of the supporting means of a variable magnitude so as to induce periodic motion of the sample, and means for actuating the displacement means in response to the sample motion, the actuating means comprising the weighted part attached to the other end of the sample and switching means responSive to the motion of the weighted part operatively connected to the displacement means, so as to achieve a steady state oscillation of the sample.
Claim 2
Independent Claim
118 words
An apparatus for determining the mechanical design properties of elastic materials comprising: means for supporting a sample, the means holding the sample at one end thereof, a weighted part attached to the other end of the sample, and means for producing a periodic transient displacement of the supporting means of a variable magnitude so as to induce periodic motion of the sample, and means for actuating the displacement means in response to the sample motion, the actuating means comprising the weighted part attached to the other end of the sample and switching means responSive to the motion of the weighted part operatively connected to the displacement means, so as to achieve a steady state oscillation of the sample.
Claim 3
Dependent Claim
47 words
The apparatus of claim 1 in which the sample is a strip having a length l at least 12 times its thickness h and in which the oscillation comprises a uniform cyclic bending of the strip about a bend axis transverse to the length of the strip.
Claim 4
Dependent Claim
218 words
The apparatus of claim 2 in which: the sample strip supporting means comprises at least two supporting members, a base plate, two blocks mounted near opposite edges of the base plate and on a center line through the center of gravity of the base plate, the blocks rotatably mounted on the supporting members so as to achieve rotation of the base plate about an axis of rotation displaced from but parallel to the center line of the base plate, the base plate defining two parallel slot shaped apertures, the long dimensions of the apertures being normal to the axis of rotation of the base plate, and a first holder mounted on the base plate between the apertures and on the center line of the base plate; the weighted part comprises a second holder and two elongated members of substantially equal weight and dimensions attached to opposite ends of the holder and extending through the apertures, the center of gravity of the weighted part being approximately on the displaced axis of rotation of the base plate, and the displacement means comprises at least one solenoid movably mounted near one end of the base plate, so that actuating the solenoid produces an attractive force upon the base plate and causes a resultant rotation of the base plate toward the solenoid.
Claim 5
Dependent Claim
65 words
The apparatus of claim 3 in which the means for actuating the solenoid comprises at least one optical switch movably mounted within the path of rotation of the attachment part and circuit means for controlling the interaction between the optical switch and the solenoid so that traversal of the optical switch by the weighted part results in the alternate actuation and deactuation of the solenoid.
Claim 6
Independent Claim
85 words
A method for determining the mechanical design properties of elastic materials comprising: supporting a sample at one end, attaching a weighted part to the other end of the sample, producing a periodic transient displacement of the supported end of the sample so as to induce periodic motion of the sample, the magnitude of the displacement being of a predetermined value, and the period of the displacement being determined by the period of the sample, so as to achieve a steady state oscillation of the sample.
Claim 7
Independent Claim
85 words
A method for determining the mechanical design properties of elastic materials comprising: supporting a sample at one end, attaching a weighted part to the other end of the sample, producing a periodic transient displacement of the supported end of the sample so as to induce periodic motion of the sample, the magnitude of the displacement being of a predetermined value, and the period of the displacement being determined by the period of the sample, so as to achieve a steady state oscillation of the sample.
Claim 8
Dependent Claim
201 words
The method of claim 5 in which the transient displacement produced is angular, and its magnitude is determined by the relationship: theta o 2l/h Delta epsilon where l is the length of the sample, h is the thickness of the sample, and Delta epsilon is the desired maximum permanent deformation, and in which the design modulus is related to the steady state frequency of oscillation of the sample E 473.7 lJ/bh3 f2 wherein E is the design modulus, l is the sample length, b is the sample width, h is the sample thickness, J is the mass moment of inertia of the attachment part, and f is the measured frequency of rotation of the part, and the design stress is related to the steady state amplitude of oscillation of the sample according to: sigma 1 E ( epsilon 1 - Delta epsilon ) where sigma 1 is the design stress, E is the design modulus, Delta epsilon is the offset, and epsilon 1 is the design strain which is a function of the steady state amplitude of the angle of rotation according to the relationship: epsilon 1 0.00759 (h/l) phi a where phi a is the steady state or maximum amplitude.
Claim 9
Dependent Claim
46 words
The method of claIm 5 in which the sample is a strip having a length at least 12 times its thickness h and in which the oscillation comprises a uniform cyclic bending of the strip about a bend axis transverse to the length of the strip.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |