US4900291A — Bicycle gear shifting method and apparatus

Claim 1

Independent Claim 150 words

A bicycle derailleur gear shifting system, which comprises: derailleur shifting means having return spring means operatively associated with the rear wheel of the bicycle; handgrip shift actuator cam means rotatably mounted on the bicycle handlebar generally coaxially of the handlebar; control cable means having one end operatively associated with said cam means and the other end operatively connected to said derailleur shifting means, said cable means being biased toward said derailleur shifting means by said return spring means; said cam means being configured so that rotational movement thereof in one direction will cause said cam means to pull said cable means against the biasing force of said spring means so as to cause down-shifting of said shifting means, and rotation thereof in the opposite direction will release said cable means in the direction of the biasing force of said spring means so as to cause up-shifting of said shifting means.

Claim 2

Dependent Claim 150 words

A bicycle derailleur gear shifting system, which comprises: derailleur shifting means having return spring means operatively associated with the rear wheel of the bicycle; handgrip shift actuator cam means rotatably mounted on the bicycle handlebar generally coaxially of the handlebar; control cable means having one end operatively associated with said cam means and the other end operatively connected to said derailleur shifting means, said cable means being biased toward said derailleur shifting means by said return spring means; said cam means being configured so that rotational movement thereof in one direction will cause said cam means to pull said cable means against the biasing force of said spring means so as to cause down-shifting of said shifting means, and rotation thereof in the opposite direction will release said cable means in the direction of the biasing force of said spring means so as to cause up-shifting of said shifting means.

Claim 3

Dependent Claim 29 words

A bicycle derailleur gear shifting system as defined in claim 1, wherein said cam means is engaged over the outside of the handlebar proximate an end of the handlebar.

Claim 4

Dependent Claim 31 words

A bicycle derailleur gear shifting system as defined in claim 1, wherein said cam means is engaged over the outside of the handlebar substantially inboard of an end of the handlebar.

Claim 5

Dependent Claim 39 words

A bicycle derailleur gear shifting system as defined in claim 1, wherein said cam means is configured so as to substantially compensate for increasing force of said return spring means in the down-shifting direction of said derailleur shifting means.

Claim 6

Dependent Claim 35 words

A bicycle derailleur gear shifting system as defined in claim 1, wherein said cam means is configured so as to substantially compensate for the lost motions in said derailleur shifting means and said cable means.

Claim 7

Dependent Claim 34 words

A bicycle derailleur gear shifting system as defined in claim 5, wherein said cable means embodies housing means which is substantially compressionless, thereby making lost motion in said cable means small and substantially predictable.

Claim 8

Dependent Claim 70 words

A bicycle derailleur gear shifting system as defined in claim 5, wherein said derailleur shifting means is a rear derailleur shifting means, and said cable means comprises a first relatively short cable housing section proximate said cam means and a second relatively short cable housing section proximate said derailleur shifting means, with a relatively long unhoused length of said cable means extending between said first and second cable housing sections.

Claim 9

Dependent Claim 58 words

A bicycle derailleur gear shifting system as defined in claim 5, wherein said derailleur shifting means is a front derailleur shifting means, and said cable means comprises a relatively short cable housing section proximate said cam means, with a relatively long unhoused length of said cable means extending between said cable housing section and said derailleur shifting means.

Claim 10

Dependent Claim 31 words

A bicycle derailleur gear shifting system as defined in claim 1, wherein said cam means is configured so as to substantially compensate for chain gap variations in said derailleur shifting means.

Claim 11

Dependent Claim 78 words

A bicycle derailleur gear shifting system as defined in claim 1, wherein said derailleur shifting means is a rear derailleur shifting means, and said cam means is configured so as to cause said derailleur shifting means to move the bicycle chain a sufficient amount beyond the destination freewheel sprocket of said derailleur shifting means in a down-shifting event so that the chain will approach the destination sprocket in the same direction as it would in an up-shifting event.

Claim 12

Dependent Claim 36 words

A bicycle derailleur gear shifting system as defined in claim 10, wherein said cam means is configured so that said movement of the bicycle chain beyond said destination sprocket is insufficient to cause a double shift.

Claim 13

Dependent Claim 49 words

A bicycle derailleur gear shifting system as defined in claim 10, wherein said destination sprocket is the largest freewheel sprocket, and said cam means is configured so that movement of the bicycle chain beyond said destination sprocket is insufficient to cause the chain to derail from said destination sprocket.

Claim 14

Dependent Claim 45 words

A bicycle derailleur gear shifting system as defined in claim 10, wherein said cam means is configured so that said movement of the bicycle chain beyond said destination sprocket is insufficient to cause the chain to rasp against the next sprocket beyond said destination sprocket.

Claim 15

Dependent Claim 80 words

A bicycle derailleur gear shifting system as defined in claim 1, wherein said derailleur shifting means is a front derailleur shifting means, and said cam means is configured with first and second locations which causes said derailleur shifting means to substantially align the bicycle chain with respective first and second derailleur chain wheels during parallel riding, and a third location which causes said derailleur shifting means to substantially align the chain with one of said chain wheels during cross-over riding.

Claim 16

Dependent Claim 41 words

A bicycle derailleur gear shifting system as defined in claim 14, wherein said cam means is configured with a fourth location which causes said derailleur shifting means to substantially align the chain with the other said chain wheel during cross-over riding.

Claim 17

Dependent Claim 106 words

In a bicycle derailleur gear shifting system having a rear derailleur shifting mechanism, a shift actuator, and control cable means operatively connecting said actuator to said shifting mechanism, a method of performing down-shifting events from a relatively smaller origin freewheel sprocket to a relatively larger destination freewheel sprocket, which comprises: first moving said shift actuator a sufficient amount to take up substantially all of the cumulative lost motion in said derailleur mechanism and said cable means; and then moving said shift actuator a further amount to as to move the bicycle chain at least substantially the distance between the centers of said origin and destination sprockets.

Claim 18

Dependent Claim 106 words

In a bicycle derailleur gear shifting system having a rear derailleur shifting mechanism, a shift actuator, and control cable means operatively connecting said actuator to said shifting mechanism, a method of performing down-shifting events from a relatively smaller origin freewheel sprocket to a relatively larger destination freewheel sprocket, which comprises: first moving said shift actuator a sufficient amount to take up substantially all of the cumulative lost motion in said derailleur mechanism and said cable means; and then moving said shift actuator a further amount to as to move the bicycle chain at least substantially the distance between the centers of said origin and destination sprockets.

Claim 19

Dependent Claim 30 words

A method according to claim 16, which comprises minimizing said cumulative lost motion and making it more predictable by providing said cable means with housing means that is substantially compressionless.

Claim 20

Dependent Claim 35 words

A method according to claim 17, which comprises further minimization of said cumulative lost motion by providing said cable means with relatively short cable housing means and a relatively long cable portion that is unhoused.

Claim 21

Dependent Claim 27 words

A method according to claim 16, which comprises moving said shift actuator a sufficient amount to substantially compensate for chain gap variations in said derailleur shifting means.

Claim 22

Dependent Claim 67 words

A method according to claim 16, which comprises first moving said shift actuator a sufficient amount to cause the bicycle chain to first move beyond said destination sprocket, and then moving said shift actuator back to cause the chain to move back to substantial alignment with said destination sprocket, whereby the chain approaches the destination sprocket in the same direction as it would in an up-shifting event.

Claim 23

Dependent Claim 25 words

A method according to claim 20, wherein the bicycle chain is not moved beyond said destination sprocket a sufficient amount to cause a double shift.

Claim 24

Dependent Claim 40 words

A method according to claim 20, wherein said destination sprocket is the largest freewheel sprocket, and wherein the bicycle chain is not moved beyond said destination sprocket a sufficient amount to cause the chain to derail from said destination sprocket.

Claim 25

Dependent Claim 34 words

A method according to claim 20, wherein the bicycle chain is not moved beyond said destination sprocket a sufficient amount to cause the chain to rasp against the next sprocket beyond said destination sprocket.

Claim 26

Dependent Claim 24 words

A method according to claim 16, wherein said shift actuator comprises cam means rotatably mounted on the bicycle handlebar generally coaxially of the handlebar.

Claim 27

Dependent Claim 101 words

In a bicycle derailleur gear shifting system having a front derailleur shifting mechanism having a chain cage, a shift actuator, and control cable means operatively connecting said actuator to said shifting mechanism, a method of compensating for chain misalignment during cross-over riding, which comprises: first moving said actuator an amount which would be sufficient to substantially align the bicycle chain with one of the front derailleur chain wheels during parallel riding; and then moving said actuator a further amount to move the chain toward another of said chain wheels to compensate for cross-over riding and minimize chain rasp against said cage.

Claim 28

Dependent Claim 101 words

In a bicycle derailleur gear shifting system having a front derailleur shifting mechanism having a chain cage, a shift actuator, and control cable means operatively connecting said actuator to said shifting mechanism, a method of compensating for chain misalignment during cross-over riding, which comprises: first moving said actuator an amount which would be sufficient to substantially align the bicycle chain with one of the front derailleur chain wheels during parallel riding; and then moving said actuator a further amount to move the chain toward another of said chain wheels to compensate for cross-over riding and minimize chain rasp against said cage.

Claim 29

Dependent Claim 24 words

A method according to claim 25, wherein said shift actuator comprises cam means rotatably mounted on the bicycle handlebar generally coaxially of the handlebar.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1993-02-12	1993-08-14	1994-02-13	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1997-02-12	1997-08-14	1998-02-13	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2001-02-12	2001-08-14	2002-02-13	$7700.00	Window Closed / Lapsed

Bicycle gear shifting method and apparatus

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