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US4777829A Expired / Lapsed US ⏱️ 0.0 years remaining

Multi-station piezoelectric load cycle counter

Assignee: Bridgestone Firestone Inc
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Filing: 1987-10-02
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Granted: 1988-10-18
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Expires: 2007-10-02
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Abstract

Abstract A piezoelectric load cycle counter is provided for a multi-stationed strain-life tester. A plurality of test specimens are interposed between a fixed upper bracket and a lower reciprocating bracket and are cyclically flexed therebetween. Piezoelectric crystals maintained in association with the upper bracket with each of the test stations present an output signal on each flexure of the test specimen. These output signals enable a counter which counts the number of cycles of the lower bracket. When a specimen breaks, the output signal of the associated station terminates and the count for that station similarly terminates.

Inventors

  • 👤 Thomas S. Fleischman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 07:19
CPC Classifications
G; G01; G01N; G01N3/00; G01N3/32; G01N3/02; G01N3/06; G01N3/066; G01N2203/00; G01N2203/02; G01N2203/06; G01N2203/0617; G01N2203/0623

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 139 words
A cycle counter for testing elastomeric specimens, comprising: a stationary bracket; a reciprocating bracket adapted for cyclic reciprocating movement toward and away from said stationary bracket; first circuit means connected to said reciprocating bracket for controlling cycles of said reciprocating movement and presenting a first output signal at each such cycle; a test specimen of elastomeric material interconnected between said stationary and reciprocating brackets, said test specimen being stretched by said reciprocating movement; sensing means maintained at said stationary bracket and interconnected with said test specimen for generating a second output signal corresponding to a force applied thereto through said test specimen; and second circuit means connected to said first circuit means and said sensing means, receiving said first and second output signals, and determining therefrom the number of said cycles endured by said test specimen until failure thereof.
Claim 2
Dependent Claim 139 words
A cycle counter for testing elastomeric specimens, comprising: a stationary bracket; a reciprocating bracket adapted for cyclic reciprocating movement toward and away from said stationary bracket; first circuit means connected to said reciprocating bracket for controlling cycles of said reciprocating movement and presenting a first output signal at each such cycle; a test specimen of elastomeric material interconnected between said stationary and reciprocating brackets, said test specimen being stretched by said reciprocating movement; sensing means maintained at said stationary bracket and interconnected with said test specimen for generating a second output signal corresponding to a force applied thereto through said test specimen; and second circuit means connected to said first circuit means and said sensing means, receiving said first and second output signals, and determining therefrom the number of said cycles endured by said test specimen until failure thereof.
Claim 3
Dependent Claim 15 words
The cycle counter according to claim 1 wherein said sensing means comprises a piezoelecric crystal.
Claim 4
Dependent Claim 27 words
The cycle counter according to claim 2 wherein said piezoelectric crystal is maintained between first and second insulators, said first insulator being received by said stationary bracket.
Claim 5
Dependent Claim 29 words
The cycle counter according to claim 3 wherein said second insulator is operatively connected to said test specimen and adapted for relative movement with respect to said first insulator.
Claim 6
Dependent Claim 19 words
The cycle counter according to claim 4 wherein said relative movement is induced by said test specimen being flexed.
Claim 7
Dependent Claim 29 words
The cycle counter according to claim 2 wherein said second circuit means comprises a counter, said counter being activated by a coincidence of said first and second output signals.
Claim 8
Dependent Claim 30 words
The cycle counter according to claim 6 wherein said second circuit means further comprises a first monostable multivibrator receiving said second output signal and generating a fixed amplitude signal therefrom.
Claim 9
Dependent Claim 44 words
The cycle counter according to claim 7 wherein said second output signal is sinusoidal and wherein said second circuit means further comprises a squaring circuit interposed between said piezoelectric crystal and said first monostable multivibrator for receiving and squaring said sinusoidal second output signal.
Claim 10
Dependent Claim 31 words
The cycle counter according to claim 8 wherein said second circuit means further comprises a second monstable multivibrator receiving said first output signal and generating a pulse of fixed duration therefrom.
Claim 11
Dependent Claim 30 words
The cycle counter according to claim 9 wherein said second circuit means comprises a logic AND gate connected to said counter and receiving inputs from said first and second multivibrators.
Claim 12
Dependent Claim 106 words
Elastomeric testing apparatus, comprising: a stationary member; a reciprocating member; a test specimen of elastomeric material interconnected between said stationary and reciprocating members, said test specimen cyclically stretched by reciprocating movement of said reciprocating member; a piezoelectric crystal operatively connected to said test specimen and generating a first output signal as a function of said stretching of said reciprocating member; circuit means receiving said first output signal and counting a number of cycles said test specimen is stretched until failure of said test specimen; and a control circuit connected to and controlling cycling of said reciprocating member and generating a sync pulse on each cycle thereof.
Claim 13
Dependent Claim 106 words
Elastomeric testing apparatus, comprising: a stationary member; a reciprocating member; a test specimen of elastomeric material interconnected between said stationary and reciprocating members, said test specimen cyclically stretched by reciprocating movement of said reciprocating member; a piezoelectric crystal operatively connected to said test specimen and generating a first output signal as a function of said stretching of said reciprocating member; circuit means receiving said first output signal and counting a number of cycles said test specimen is stretched until failure of said test specimen; and a control circuit connected to and controlling cycling of said reciprocating member and generating a sync pulse on each cycle thereof.
Claim 14
Dependent Claim 27 words
The elastomeric testing apparatus according to claim 11 wherein said circuit means comprises a counter activated by concurrence of said sync pulse and said first output signal.
Claim 15
Dependent Claim 52 words
The elastomeric testing apparatus according to claim 12 wherein said first output signal is of varying amplitude and wherein said circuit means includes a first multivibrator interposed between said piezoelectric crystal and said counter, said first multivibrator generating a fixed level signal in response to continued presence of said first output signal.
Claim 16
Dependent Claim 28 words
The elastomeric testing apparatus according to claim 13 wherein said circuit means further comprises a second multivibrator receiving said sync pulse and generating a fixed duration pulse therefrom.
Claim 17
Dependent Claim 35 words
The elastomeric testing apparatus according to claim 14 wherein said circuit means further comprises a logic AND gate connected to said counter and receiving said fixed level signal and fixed duration pulse as inputs thereto.
Claim 18
Dependent Claim 34 words
The elastomeric testing apparatus according to claim 11 wherein said piezoelectric crystal is maintained between first and second insulators at said stationary member, said first insulator adapted for movement relative to said second insulator.
Claim 19
Dependent Claim 16 words
The elastomeric testing apparatus according to claim 16 wherein said piezoelectric crystal is an annular disk.

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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) 1991-10-18 1992-04-18 1992-10-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-10-18 1996-04-18 1996-10-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-10-18 2000-04-18 2000-10-18 $7700.00 Window Closed / Lapsed

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