Bicycle gear shift

Claim 2

A bicycle gear shift including, in combination; a. a first gear; b. a gear cluster including at least two gears of different numbers of teeth in coaxial side-by-side relationship; c. a bicycle chain passing over said first gear and one of said gears in said gear cluster; d. derailleur means; and, e. actuating means for actuating said derailleur means to shift the chain from said one of the gears in said cluster to the next adjacent gear when said actuating means is positively moved in one direction and to shift the chain from said next adjacent gear back to said one gear when said actuating means is positively moved in an opposite direction, said derailleur means including a cam means; a carriage including a cam follower engaging said cam means, movement of said cam means relative to said cam follower causing a transverse movement of said carriage, said carriage supporting guide means for said chain to thereby effect shifting of the chain from a position in alignment with one gear to a position in alignment with a next adjacent gear, reverse movement of said cam means retracting said cam follower to cause a transverse movement of said carriage in an opposite direction to thereby effect shifting of the chain from a position in alignment with said next adjacent gear to a position in alignment with said one gear, said cam means being connected to said actuating means for movement thereby.

Claim 3

The subject matter of claim 1, in which said actuating means includes a continuous cable passing through said derailleur means, the derailleur means being actuated in response to movement of said cable through a given distance; and manually operable means for positively moving said cable in said one direction and in said opposite direction, respectively.

Claim 4

The subject matter of claim 1, in which said cam means comprises a cylindrical member mounted for rotation about an axis parallel to the axis of said gear cluster, said member including a peripheral groove starting adjacent to one side of the member and following an alternate helical and circumferential path towards the other side of the member, said cam follower comprising a cam pin on said carriage received in said groove.

Claim 5

A bicycle gear shift including, in combination; a. a front gear cluster comprised of coaxial front gears in side-by-side relationship rotatable by the pedals of said bicycle; b. a rear gear cluster comprised of coaxial rear gears in side-by-side relationship rotatable with the rear wheel of said bicycle; c. a bicycle chain passing over one of the front gears and one of the rear gears; d. a front derailleur means for shifting the chain from one gear to a next adjacent gear in said front gear cluster upon actuation; e. a rear derailleur means for shifting the chain from one gear to a next adjacent gear in said rear cluster upon actuation; f. a single continuous actuating cable passing through the front and rear derailleur means in series, the front derailleur means being actuated in response to movement of said cable through a first given distance and the rear derailleur means being actuated in response to movement of said cable through a second given distance; g. manually operable means on a portion of the frame for moving said cable through said first given distance each time the manually operable means is operated; and, h. scalE means and cooperating marker means for indicating gear positions, relative movement between said scale means and marker means taking place in response to movement of said cable whereby a particular gear position is visually indicated.

Claim 6

A bicycle gear shift including, in combination; a. a front gear cluster comprised of coaxial front gears in side-by-side relationship rotatable by the pedals of said bicycle; b. a rear gear cluster comprised of coaxial rear gears in side-by-side relationship rotatable with the rear wheel of said bicycle; c. a bicycle chain passing over one of the front gears and one of the rear gears; d. a front derailleur means for shifting the chain from one gear to a next adjacent gear in said front gear cluster upon actuation; e. a rear derailleur means for shifting the chain from one gear to a next adjacent gear in said rear cluster upon actuation; f. a single continuous actuating cable passing through the front and rear derailleur means in series, the front derailleur means being actuated in response to movement of said cable through a first given distance and the rear derailleur means being actuated in response to movement of said cable through a second given distance; g. manually operable means on a portion of the frame for moving said cable through said first given distance each time the manually operable means is operated; and, h. scalE means and cooperating marker means for indicating gear positions, relative movement between said scale means and marker means taking place in response to movement of said cable whereby a particular gear position is visually indicated.

Claim 7

The subject matter of claim 4, including manually operable first and second ratchet lever means for moving said cable through successive distances each of which corresponds to said first given distance in one direction upon successive operation of said first ratchet lever, and for moving said cable through successive distances, each of which corresponds to said first given distance in an opposite direction upon successive operation of said second ratchet lever, successive movement of said first ratchet lever successively increasing the gear ratio and successive movement of said second ratchet lever successively decreasing the gear ratio.

Claim 8

In combination with a bicycle having a frame structure mounting handlebars, pedals, and front and rear wheels, an improved gear shift including: a. a front gear cluster including two gears having N1 and N2 teeth respectively, different in number from each other, coaxially mounted in side-by-side relationship and coupled for rotation by the bicycle pedals; b. a rear gear cluster including at least two gears having n1 and n2 teeth respectively, different in number from each other coaxially mounted together in side-by-side relationship and coupled to rotate said rear wheel; c. a bicycle chain passing over one of the gears in the front gear cluster and one of the gears in the rear gear cluster; d. a front derailleur means coupled to the bicycle frame structure and to said bicycle chain associated with said front gear cluster; e. a rear derailleur means coupled to the bicycle frame structure and to said bicycle chain associated with said rear gear cluster; f. a manually operable lever means mounted on the bicycle for manual operation by a bicycle rider while holding said handlebars; and, g. a single continuous actuating cable passing from said lever means through the front and rear derailleur means in series and back to said lever means such that each actuation of said lever means moves said cable a given distance, a first given length of said cable having a first series of spaced enlargements separated by said given distance for actuating said front derailleur means when an enlargement passes therethrough, and a second given length of said cable having a second series of spaced enlargements, separated by twice said given distance for actuating said rear derailleur means when an enlargement passes therethrough, said front derailleur means functioning upon each actuation to shift said chain from one of the two gears in said front gear cluster to the other, and said rear derailleur means functioning upon actuation to shift said chain from one of the gears in said rear gear cluster to the next adjacent gear, said rear derailleur means only being actuated once for every two actuations of said lever means.

Claim 9

In combination with a bicycle having a frame structure mounting handlebars, pedals, and front and rear wheels, an improved gear shift including: a. a front gear cluster including two gears having N1 and N2 teeth respectively, different in number from each other, coaxially mounted in side-by-side relationship and coupled for rotation by the bicycle pedals; b. a rear gear cluster including at least two gears having n1 and n2 teeth respectively, different in number from each other coaxially mounted together in side-by-side relationship and coupled to rotate said rear wheel; c. a bicycle chain passing over one of the gears in the front gear cluster and one of the gears in the rear gear cluster; d. a front derailleur means coupled to the bicycle frame structure and to said bicycle chain associated with said front gear cluster; e. a rear derailleur means coupled to the bicycle frame structure and to said bicycle chain associated with said rear gear cluster; f. a manually operable lever means mounted on the bicycle for manual operation by a bicycle rider while holding said handlebars; and, g. a single continuous actuating cable passing from said lever means through the front and rear derailleur means in series and back to said lever means such that each actuation of said lever means moves said cable a given distance, a first given length of said cable having a first series of spaced enlargements separated by said given distance for actuating said front derailleur means when an enlargement passes therethrough, and a second given length of said cable having a second series of spaced enlargements, separated by twice said given distance for actuating said rear derailleur means when an enlargement passes therethrough, said front derailleur means functioning upon each actuation to shift said chain from one of the two gears in said front gear cluster to the other, and said rear derailleur means functioning upon actuation to shift said chain from one of the gears in said rear gear cluster to the next adjacent gear, said rear derailleur means only being actuated once for every two actuations of said lever means.

Claim 10

The subject matter of claim 6, in which a portion of said cable runs parallel to a portion of the frame structure, there being provided a marker on said cable and a scale on the frame, whereby the various gear combinations established by the various successive positions of said cable can be discerned by observing the position of the marker relative to the scale.

Claim 11

The subject matter of claim 6, in which said lever means includes a drum means about which said cable passes such that rotation of said drum means in a first direction moves said cable in a first direction and rotation of said drum means in an opposite direction moves said cable in an opposite second direction; a first ratchet lever coupled to said drum for rotating it through a given circumferential distance to move said cable said given distance in said first direction; a second ratchet lever coupled to said drum for rotating it through said given circumferential distance in an opposIte direction to move said cable said given distance in said second direction; and indexing means for mechanically engaging said drum means at circumferentially spaced indexing points separated by said given distance to assure that said drum means is only rotated through a given number of degrees to move the cable said given distance for each stroke of one or the other of the ratchet levers.

Claim 12

The subject matter of claim 8, including first and second additional levers mounted adjacent to the handle bar grips; and first and second cables respectively coupling the additional levers to said first and second ratchet levers whereby the ratchet levers may be stroked by operation of the additional levers.

Claim 13

The subject matter of claim 6, in which said front derailleur means includes a cylindrical member rotatably mounted to said frame for rotation about a transverse axis parallel to the axis of said front gear cluster and having a peripheral camming groove over a first 180* of its surface extending from adjacent to one side of the member along a first helical path length to a point adjacent to the other side of the member and thence along a first circumferential path length adjacent to said other side, and thence back along a helical path length equal to said first helical path length to a point adjacent to said one side, and thence along a circumferential path length equal to said first circumferential path length adjacent to said one side, the camming groove continuing in like manner over the remaining 180* of said surface to connect to its starting point; a drive plate coupled to said cylindrical member and having four engagement points spaced at 90* from each other over which said first given length of said cable passes, such that when any one of said engagement points is engaged by one of said first series of enlargements as said cable is moved through said given distance, said drive plate is rotated 90* to thereby rotate said cylindrical member 90*; a first carriage having a cam follower pin received in said groove such that said carriage is shifted laterally in the axial direction of said cylindrical member in response to rotation of said member, said carriage including guide means straddling said chain and in alignment with the plane of one of said gears in the front cluster when the pin is in the grooved position adjacent said one side of said member and in alignment with the plane of the other of said gears in the front cluster when the pin is in the grooved position adjacent said other side of said member.

Claim 14

The subject matter of claim 6, in which said rear derailleur means includes a cylindrical member mounted for rotation about a transverse axis parallel to the axis of said rear gear cluster and having a peripheral camming groove over its surface extending from adjacent to one side of the member along alternate circumferential and helical path portions to a point adjacent the other side of the member, the number of circumferential path portions corresponding to the number of gears making up said rear gear cluster; a drive means for rotating said cylindrical member including a drive plate rotatably mounted to said frame and having a plurality of equally circumferentially spaced engagement points over which said second given length of said cable passes such that when any one of said engagement points is engaged by one of said second series of enlargements as said cable is moved through twice said given distance, said drive plate is rotated to thereby cause a given rotation of said cylindrical member; a rear carriage having a cam follower pin received in said grooves such that said carriage is shifted laterally in the axial direction of said cylindrical member from one circumferential path portion to a next successive circumferential path portion in response to each given rotation of said cylindrical member, said carriage carrying idler gear means over which said chain passes; main pivot arm means mounting said cylindrical member and carriage to said frame for swinging movement about a transverse axis parallel to the axis of the rear gear cluster; parallelogram coupling means mounting said carriage to said main pivot means to permit transverse movement of said carriage; and, auxiliary pivot means mounting said idler gear means to said carriage for swinging movement about an axis parallel to the axis of said rear gear cluster relative to the carriage, whereby transverse movement of the carriage moves the idler gear means transversely to align said chain with a next adjacent gear in the rear gear cluster, said main pivot arm means and said auxiliary pivot means being biased to swing in a manner to maintain the chain in proper alignment with the periphery of any particular gear over which it passes and to maintain a tension in the chain, respectively.

Claim 15

The subject matter of claim 11, in which said drive means includes a cable drum coupled for rotation by said drive plate; and an auxiliary flexible cable passing about said cable drum and said cylindrical member to rotate said cylindrical member upon rotation of said drum by said drive plate, said flexible cable accommodating swinging movement of said main pivot arm means.

Claim 16

The subject matter of claim 6, in which said rear gear cluster includes a total of five gears, the three gears in addition to said first mentioned two gears having n3, n4, and n5 teeth respectively, different from each other and from n1 and n2, the chain engaging front and rear gears in the following sequence for each successive actuation of said manually operable lever means starting at the lowest gear ratio to the highest wherein there are ten gear positions and wherein N1>N2 and n1>n2>n3>n4>n5: