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US4121623A Expired / Lapsed US ⏱️ 0.0 years remaining

Spacer for concentric tubes

Assignee: KM Kabelmetal AG
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Filing: 1976-07-02
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Granted: 1978-10-24
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Expires: 1996-07-02
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Abstract

Abstract The spacer is helically wound on the inner one of two concentric tubes, and is constructed from plural elongated, generally flat members of different cross-section and profile for surface contours permitting only limited contact between adjacent members. Alternation between convex and concave surfaces prevents lateral shifting of the members off each other.

Inventors

  • 👤 Peter Rhone

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 02:47
CPC Classifications
H; H01; H01B; H01B12/00; H01B12/14; F; F16; F16L; F16L59/00; F16L59/12; F16L59/125; F16L59/14; F16L59/141; Y; Y02; Y02E; Y02E40/00; Y02E40/60; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/884; Y10S505/885; Y10S505/886

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 104 words
A spacer for a coaxial tube system having an inner tube and an outer tube, the spacer being helically wound on the inner tube for holding the inner tube in and concentric to the outer tube, comprising: a plurality of superposed elongated members adjacent ones of which have different cross-sections defining pairs of engaging, differently contoured, non-mating surfaces which are shaped to permit a stable engagement between pairs with a minimum of contact therebetween, and wherein at least one of said pairs is formed by cross-sections defining a convex surface facing and in engagement with at least two spaced points of a concave surface.
Claim 2
Dependent Claim 104 words
A spacer for a coaxial tube system having an inner tube and an outer tube, the spacer being helically wound on the inner tube for holding the inner tube in and concentric to the outer tube, comprising: a plurality of superposed elongated members adjacent ones of which have different cross-sections defining pairs of engaging, differently contoured, non-mating surfaces which are shaped to permit a stable engagement between pairs with a minimum of contact therebetween, and wherein at least one of said pairs is formed by cross-sections defining a convex surface facing and in engagement with at least two spaced points of a concave surface.
Claim 3
Dependent Claim 19 words
A spacer as in claim 1, having at least three members, of which at least two differ in cross-section.
Claim 4
Dependent Claim 18 words
A spacer as in claim 1, wherein respective adjacent ones of the members are made of different materials.
Claim 5
Dependent Claim 16 words
A spacer as in claim 1, wherein the members change cross-section in longitudinal direction of extension.

References Cited (Backward Citations)

US319738A Cited
US3473575A Cited
US3595275A Cited
US3592238A Cited
US3670772A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-23 1982-04-24 1982-10-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-23 1986-04-24 1986-10-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-23 1990-04-24 1990-10-24 $7700.00 Window Closed / Lapsed

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