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US5326524A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making plastic rods

Assignee: Phillips Petroleum Co
•
Filing: 1990-03-23
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Granted: 1994-07-05
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Expires: 2010-03-23
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Abstract

Abstract In bending rods reinforced with continuous fibers, buckling or stretching of reinforcing fibers is reduced by conforming the continuous fibers to a helical configuration within the rods before or when the rods are bent. The helical configuration causes fibers near the surface of the rod to travel substantially the same distance when the rod is bent whether the fibers are on the inside radius or the outside radius of the bend.

Inventors

  • 👤 Vergil H. Rhodes, Jr.
  • 👤 John D. Winkel
  • 👤 Benedict R. Bonazza

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 13:35
CPC Classifications
B; B29; B29C; B29C53/00; B29C53/02; B29C53/08; B29C53/083; B29K; B29K2105/00; B29K2105/06; B29K2105/08; B29K2105/10; B29K2105/101; B29K2105/108; B29L; B29L2031/00; B29L2031/06

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 144 words
A method for making fiber reinforced plastic rods to minimize tensioning and buckling of continuous reinforcing fibers when said rods are bent, said method comprising: (a) heating a rod having longitudinally arranged continuous reinforcing fibers; and (b) twisting said rod to rotate said continuous reinforcing fibers about the longitudinal axis of said rod, thereby conforming said continuous reinforcing fibers into helices according to the formula: ##EQU9## wherein φ=number of helices, expressed in radians, per unit length R=inside radius of a bend to be postformed in said rod d=diameter of said rod Θ=radians of said bend to be postformed about said inside radius x=a non-zero real number and R and d are expressed in consistent units of length, whereby said bend postformed to said twisting is limited as to said inside radius of said bend and the radians of said bend about said inside radius.
Claim 2
Independent Claim 144 words
A method for making fiber reinforced plastic rods to minimize tensioning and buckling of continuous reinforcing fibers when said rods are bent, said method comprising: (a) heating a rod having longitudinally arranged continuous reinforcing fibers; and (b) twisting said rod to rotate said continuous reinforcing fibers about the longitudinal axis of said rod, thereby conforming said continuous reinforcing fibers into helices according to the formula: ##EQU9## wherein φ=number of helices, expressed in radians, per unit length R=inside radius of a bend to be postformed in said rod d=diameter of said rod Θ=radians of said bend to be postformed about said inside radius x=a non-zero real number and R and d are expressed in consistent units of length, whereby said bend postformed to said twisting is limited as to said inside radius of said bend and the radians of said bend about said inside radius.
Claim 3
Independent Claim 143 words
A method for making fiber reinforced plastic rods to minimize tensioning and buckling of continuous reinforcing fibers when said rods are bent, said method comprising: (a) heating a rod having longitudinally arranged continuous reinforcing fibers; and (b) twisting said rod to rotate said continuous reinforcing fibers about the longitudinal axis of said rod, thereby conforming said continuous reinforcing fibers into helices according to the formula: ##EQU10## wherein φ=number of helices, expressed in radians, per unit length R=inside radius of a bend to be postformed in said rod d=diameter of said rod Θ=radians of said bend to be postformed about said inside radius x=a non-zero integer and R and d are expressed in consistent units of length, whereby said bend postformed to said twisting is limited as to said inside radius of said bend and the radians of said bend about said inside radius.
Claim 4
Independent Claim 143 words
A method for making fiber reinforced plastic rods to minimize tensioning and buckling of continuous reinforcing fibers when said rods are bent, said method comprising: (a) heating a rod having longitudinally arranged continuous reinforcing fibers; and (b) twisting said rod to rotate said continuous reinforcing fibers about the longitudinal axis of said rod, thereby conforming said continuous reinforcing fibers into helices according to the formula: ##EQU10## wherein φ=number of helices, expressed in radians, per unit length R=inside radius of a bend to be postformed in said rod d=diameter of said rod Θ=radians of said bend to be postformed about said inside radius x=a non-zero integer and R and d are expressed in consistent units of length, whereby said bend postformed to said twisting is limited as to said inside radius of said bend and the radians of said bend about said inside radius.
Claim 5
Independent Claim 148 words
A method for making fiber reinforced plastic rods to minimize tensioning and buckling of continuous reinforcing fibers when said rods are bent, said method comprising: (a) heating a rod having longitudinally arranged continuous reinforcing fibers; and (b) twisting said rod to rotate said continuous reinforcing fibers about the longitudinal axis of said rod, thereby conforming said continuous reinforcing fibers into helices according to the formula: ##EQU11## wherein φ min =minimize number of helices, expressed in radians, per unit length needed to provide optimum improvement R=inside radius of a bend to be postformed in said rod d=diameter of said rod Θ=radians of said bend to be postformed about said inside radius and R and d are expressed in consistent units of length, whereby said bend postformed to said twisting is limited as to said inside radius of said bend and the radians of said bend about said inside radius.
Claim 6
Independent Claim 148 words
A method for making fiber reinforced plastic rods to minimize tensioning and buckling of continuous reinforcing fibers when said rods are bent, said method comprising: (a) heating a rod having longitudinally arranged continuous reinforcing fibers; and (b) twisting said rod to rotate said continuous reinforcing fibers about the longitudinal axis of said rod, thereby conforming said continuous reinforcing fibers into helices according to the formula: ##EQU11## wherein φ min =minimize number of helices, expressed in radians, per unit length needed to provide optimum improvement R=inside radius of a bend to be postformed in said rod d=diameter of said rod Θ=radians of said bend to be postformed about said inside radius and R and d are expressed in consistent units of length, whereby said bend postformed to said twisting is limited as to said inside radius of said bend and the radians of said bend about said inside radius.
Claim 7
Dependent Claim 58 words
A method as recited in claim 1 further comprising: (c) heating said rod where said bend is to be made; and (d) forming said bend in said rod, said bend having an inside radius of bend and radians of bend about said inside radius limited by the number of helices of continuous reinforcing fibers formed in step (b).
Claim 8
Dependent Claim 58 words
A method as recited in claim 2 further comprising: (c) heating said rod where said bend is to be made; and (d) forming said bend in said rod, said bend having an inside radius of bend and radians of bend about said inside radius limited by the number of helices of continuous reinforcing fibers formed in step (b).
Claim 9
Dependent Claim 57 words
A method as recited in claim 3 further comprising: (c) heating said rod where said bend is to be made; (d) forming said bend in said rod, said bend having an inside radius of bend and radians of bend about said inside radius limited by the number of helices of continuous reinforcing fibers formed in step (b).

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-07-04 1998-01-03 1998-07-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-07-04 2002-01-03 2002-07-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-07-04 2006-01-03 2006-07-05 $7700.00 Window Closed / Lapsed

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