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US4921267A Expired / Lapsed US ⏱️ 0.0 years remaining

Bicycle and frame therefor

Assignee: Norsk Hydro ASA
•
Filing: 1989-07-05
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Granted: 1990-05-01
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Expires: 2009-07-05
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Abstract

Abstract A light weight bicycle frame has open section, e.g. I section, parts cast in a light weight metal or alloy, preferably a magnesium alloy. A frame consists of an upper bar, and a lower bar, a saddle stem, a head, and rear forks. The bars are of I section and the saddle stem is of U section merging into or taking a tubular section receiving a saddle support tube. A structural bridge of I section interconnects the bars. The lower bar joins the saddle stem at a point intermediate the ends thereof and above the bearing for a crank wheel.

Inventors

  • 👤 Francis G. Kirk

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 17:19
CPC Classifications
B; B62; B62K; B62K19/00; B62K19/02; B62K19/04; B62K19/12; B62K3/00; B62K3/02; B62K3/04

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 158 words
A cast bicycle open frame including a cross bar, a head and a saddle stem, a lower bar linking the head and the saddle stem, a pair of rear forks having one end of each fork attached to the saddle stem, the lower bar having a longitudinal axis, the saddle stem having an intermediate portion along the length thereof, said pair of rear forks having the other end intersecting in a point of intersection, the improvement comprising the cross bar, the lower bar, the head, the saddle stem and said pair of rear forks being an integrally-formed cast frame member of lightweight metal or alloy, a structural bridge linking the cross bar and the lower bar at a location between the head and the saddle stem, the lower bar joining the saddle stem at the intermediate portion thereof such that the longitudinal axis of the lower bar intersects said point of intersection of said rear pair of forks.
Claim 2
Dependent Claim 158 words
A cast bicycle open frame including a cross bar, a head and a saddle stem, a lower bar linking the head and the saddle stem, a pair of rear forks having one end of each fork attached to the saddle stem, the lower bar having a longitudinal axis, the saddle stem having an intermediate portion along the length thereof, said pair of rear forks having the other end intersecting in a point of intersection, the improvement comprising the cross bar, the lower bar, the head, the saddle stem and said pair of rear forks being an integrally-formed cast frame member of lightweight metal or alloy, a structural bridge linking the cross bar and the lower bar at a location between the head and the saddle stem, the lower bar joining the saddle stem at the intermediate portion thereof such that the longitudinal axis of the lower bar intersects said point of intersection of said rear pair of forks.
Claim 3
Dependent Claim 15 words
The bicycle frame according to claim 1 wherein the frame member is of magnesium-based alloy.
Claim 4
Dependent Claim 17 words
The bicycle frame according to claim 1, wherein the cross bar and the lower bar are I-sections.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-04-30 1993-10-30 1994-05-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-04-30 1997-10-30 1998-05-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-04-30 2001-10-30 2002-05-01 $7700.00 Window Closed / Lapsed

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