Bicycle hub assembly and bicycle control system

A bicycle hub assembly, comprising:

• a hub shell including a braking surface;
• a hub driver;
• a coaster brake shoe accommodated in the hub shell to cooperate with the braking surface to generate braking force;
• a motor accommodated in the hub shell and configured to change a gear ratio of a rotation speed of the hub driver to a rotation speed of the hub shell;
• a hub axle at least partially covered with the hub shell,
• the hub driver directly or indirectly coupled to a driving member and rotatable in a first direction and a second direction opposite to the first direction, wherein the hub driver is rotated in the first direction when a pedal is rotated in a forward travelling direction, and wherein the hub driver is rotated in the second direction when the pedal is rotated in a direction opposite to the forward travelling direction;
• and
• a transmission device arranged inside the hub shell to convey rotation of the hub driver in the first direction to the hub shell at a selected gear ratio,
• wherein the coaster brake shoe is configured to be pressed against the braking surface by a rotary motion of the transmission device caused by rotation of the hub driver in the second direction to generate frictional braking force,
• wherein the transmission device includes the motor,
• wherein the transmission device includes an epicyclic rotor mechanism directly or indirectly coupled to each of the hub driver, the coaster brake shoe, and the motor,
• the bicycle hub assembly further comprising a first one-way clutch coupled to a first location on the epicyclic rotor mechanism,
• wherein when the hub driver is rotated in the first direction, the first one-way clutch stops conveying the rotation of the hub driver in the first direction to the coaster brake shoe so that the coaster brake shoe does not generate frictional braking force,
• wherein when the hub driver is rotated in the second direction, the first one-way clutch permits conveying the rotation of the hub driver in the second direction to the coaster brake shoe via the epicyclic rotor mechanism so that the coaster brake shoe generates frictional braking force,
• wherein the epicyclic rotor mechanism includes
• a sun rotor arranged coaxially with the hub axle,
• a plurality of planetary rotors coupled to the sun rotor,
• a carrier rotatably supporting the plurality of planetary rotors, and
• a ring rotor coupled to the plurality of planetary rotors,
• wherein the motor includes a rotary shaft coupled to the sun rotor,
• the first one-way clutch is coupled to the ring rotor and the carrier to convey rotation of the hub driver in the second direction to the coaster brake shoe via the first one-way clutch and the carrier and not to convey rotation of the hub driver in the first direction to the carrier.

A bicycle hub assembly, comprising:

• a hub shell including a braking surface;
• a hub driver;
• a coaster brake shoe accommodated in the hub shell to cooperate with the braking surface to generate braking force;
• a motor accommodated in the hub shell and configured to change a gear ratio of a rotation speed of the hub driver to a rotation speed of the hub shell,
• a hub axle at least partially covered with the hub shell;
• the hub driver directly or indirectly coupled to a driving member and rotatable in a first direction and a second direction opposite to the first direction, wherein the hub driver is rotated in the first direction when a pedal is rotated in a forward travelling direction, and wherein the hub driver is rotated in the second direction when the pedal is rotated in a direction opposite to the forward travelling direction;
• and
• a transmission device arranged inside the hub shell to convey rotation of the hub driver in the first direction to the hub shell at a selected gear ratio,
• wherein the coaster brake shoe is configured to be pressed against the braking surface by a rotary motion of the transmission device caused by rotation of the hub driver in the second direction to generate frictional braking force,
• wherein the transmission device includes the motor,
• wherein the transmission device includes an epicyclic rotor mechanism directly or indirectly coupled to each of the hub driver, the coaster brake shoe, and the motor,
• wherein the epicyclic rotor mechanism includes
• a sun rotor arranged coaxially with the hub axle,
• a plurality of planetary rotors coupled to the sun rotor,
• a carrier rotatably supporting the plurality of planetary rotors, and
• a ring rotor coupled to the plurality of planetary rotors,
• wherein the motor includes a rotary shaft coupled to the sun rotor, and
• wherein the carrier includes a cam surface arranged oppositely to the motor in an axial direction and rotatably supporting a brake roller, wherein the cam surface is shaped such that the brake roller presses the coaster brake shoe toward the braking surface in a radially outward direction when the hub driver is rotated in the second direction.

A bicycle hub assembly, comprising:

• a hub shell including a braking surface;
• a hub driver;
• a coaster brake shoe accommodated in the hub shell to cooperate with the braking surface to generate braking force;
• a motor accommodated in the hub shell and configured to change a gear ratio of a rotation speed of the hub driver to a rotation speed of the hub shell;
• a hub axle at least partially covered with the hub shell,
• the hub driver directly or indirectly coupled to a driving member and rotatable in a first direction and a second direction opposite to the first direction, wherein the hub driver is rotated in the first direction when a pedal is rotated in a forward travelling direction, and wherein the hub driver is rotated in the second direction when the pedal is rotated in a direction opposite to the forward travelling direction;
• and
• a transmission device arranged inside the hub shell to convey rotation of the hub driver in the first direction to the hub shell at a selected gear ratio,
• wherein the coaster brake shoe is configured to be pressed against the braking surface by a rotary motion of the transmission device caused by rotation of the hub driver in the second direction to generate frictional braking force,
• wherein the transmission device includes the motor,
• wherein the transmission device includes an epicyclic rotor mechanism directly or indirectly coupled to each of the hub driver, the coaster brake shoe, and the motor,
• the bicycle hub assembly further comprising:
• a first one-way clutch coupled to the hub shell and a ring rotor of the epicyclic rotor mechanism, and
• a second one-way clutch coupled to the ring rotor and a carrier of the epicyclic rotor mechanism,
• wherein the first and second one-way clutches are arranged so that
• the rotation of the hub driver in the first direction is conveyed to the hub shell via the carrier, the second one-way clutch, the ring rotor and the first one-way clutch in a sequential manner, and
• the rotation of the hub driver in the second direction is conveyed to the coaster brake shoe via the carrier without involving the ring rotor and the first and second one-way clutches.