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US4521207A Expired / Lapsed US ⏱️ 0.0 years remaining

Incrementally variable transmission

Assignee: FIRSTAR NAPER BANK NA
•
Filing: 1983-01-10
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Granted: 1985-06-04
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Expires: 2003-01-10
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Abstract

Abstract An incrementally variable transmission, particularly suitable for a bicycle, having a variable sprocket which comprises: A drive flange and an indexing flange mounted on an axle with a pair of sprocket-segment-planets and at least a pair of idler-planets sandwiched between said flanges and forming a relatively rigid structure, the planets adapted to expand and contract in response to a relative rotation of the flanges and thereby increase and decrease, respectively, the effective diameter of the variable-sprocket.

Inventors

  • 👤 Royce H. Husted

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 05:58
CPC Classifications
F; F16; F16H; F16H9/00; F16H9/02; F16H9/04; F16H9/10; B; B62; B62M; B62M9/00; B62M9/04; B62M9/06; B62M9/08

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 162 words
A variable sprocket comprising in combination: an axle, a drive flange mounted on said axle, an indexing flange rotatably mounted on said axle opposite of said drive flange and having a plurality of spiral-wavy-cams, two sprocket-segment-planets and at least two idler-planets connected to said flanges, coupling means for transmitting force between said sprocket-segment-planets and said drive flange, cam followers attached to said planets for engaging with and following said spiral-wavy-cams, said spiral-wavy-cams comprising a series of alternating depressions and hills which move said planets closer and further to and from said axle, respectively, as said planets slide along said spiral-wavy-cams, a chain made of links wrapping approximately one half of the periphery of said variable-sprocket, said sprocket-segment-planet having means for positively engaging said chain, said means comprising at least one tooth having an incline at a point of contacting said chain, said incline being steep so as to prevent said chain from disengaging from said tooth while said tooth carries chain's load.
Claim 2
Dependent Claim 162 words
A variable sprocket comprising in combination: an axle, a drive flange mounted on said axle, an indexing flange rotatably mounted on said axle opposite of said drive flange and having a plurality of spiral-wavy-cams, two sprocket-segment-planets and at least two idler-planets connected to said flanges, coupling means for transmitting force between said sprocket-segment-planets and said drive flange, cam followers attached to said planets for engaging with and following said spiral-wavy-cams, said spiral-wavy-cams comprising a series of alternating depressions and hills which move said planets closer and further to and from said axle, respectively, as said planets slide along said spiral-wavy-cams, a chain made of links wrapping approximately one half of the periphery of said variable-sprocket, said sprocket-segment-planet having means for positively engaging said chain, said means comprising at least one tooth having an incline at a point of contacting said chain, said incline being steep so as to prevent said chain from disengaging from said tooth while said tooth carries chain's load.
Claim 3
Dependent Claim 48 words
The subject matter of claim 1, wherein said planets are located, by said cam-followers seated in said depressions, so that when said sprocket-segment-planet engages said chain it takes over the chain's load from the previously engaged sprocket-segment-planet allowing the previously engaged sprocket-segment-planet to become disengaged from said chain.
Claim 4
Dependent Claim 49 words
The subject matter of claim 1, wherein the location of said planets when their cam followers are seated in said depressions and when both sprocket-segment-planets are engaged with said chain is such that the length of chain which is trapped between said sprocket-segment-planets is free of tension or slack.
Claim 5
Dependent Claim 17 words
The subject matter of claim 1, said planets being sandwiched between said drive-flange and said indexing flange.
Claim 6
Dependent Claim 21 words
The subject matter of claim 1, said planet having locking means to prevent it from separating from said spiral-wavy-cam under load.
Claim 7
Dependent Claim 22 words
The subject matter of claim 1, said sprocket-segment-planet having locking means to prevent it from separating from said drive flange under load.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-06-03 1988-12-03 1989-06-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-06-03 1992-12-03 1993-06-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-06-03 1996-12-03 1997-06-04 $7700.00 Window Closed / Lapsed

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