Bicycle drive assembly

A drive assembly for a physically propelled vehicle comprising:

• a. a drive member rotatively mounted on a drive axis,
• b. a crank arm operatively connected to the drive member for rotating the drive member,
• c. a power arm rotatively mounted for relative angular movement between the power arm and crank arm,
• d. a pedal means operatively connected to the power arm for rotating the power arm,
• e. control means interconnecting the power arm and crank arm for rotating the crank arm and drive member, and for accelerating the power arm ahead of the crank arm during one portion of the crank arm cycle and decelerating the power arm behind the crank arm during another portion of the crank arm cycle, and
• f. the control means including:
• 1. a cam slot in one of the arms, and
• 2. a cam element having a shaft rotatively mounted in the other of the arms, a cam follower spaced from the shaft and received in the cam slot, and a link between the shaft and cam follower.

A drive assembly for a physically propelled vehicle comprising:

• a. a drive member rotatively mounted on a drive axis,
• b. a crank arm operatively connected to the drive member for rotating the drive member,
• c. a power arm rotatively mounted on the drive axis for relative angular movement between the power arm and crank arm,
• d. a pedal means operatively connected to the power arm for rotating the power arm,
• e. control means interconnecting the power arm and crank arm for rotating the crank arm and drive member, and for accelerating the power arm ahead of the crank arm during one portion of the crank arm cycle and decelerating the power arm behind the crank arm during another portion of the crank arm cycle, the control means including:
• 1. a cam slot in the crank arm, and
• 2. a cam element having a shaft rotatively mounted in the power arm, a cam follower spaced from the shaft and received in the cam slot, and a link between the cam shaft and cam follower,
• f. the pedal means including a reciprocating connector pivotally connected to the power arm for rotating the power arm, the connector being attached to the cam shaft of the cam element to cause relative rotation of the cam element and power arm during rotation of the crank arm and power arm for selectively moving the power arm ahead of and behind the crank arm as the cam follower rides in the cam slot, the angular position of the cam element between the crank arm and power arm determining the position during the crank arm cycle at which the maximum angular distance occurs between the crank arm and power arm.

A drive assembly for a physically propelled vehicle comprising:

• a. a drive member rotatively mounted on a drive axis,
• b. a crank arm operatively connected to the drive member for rotating the drive member,
• c. a power arm rotatively mounted for relative angular movement between the power arm and crank arm,
• d. a pedal means operatively connected to the power arm for rotating the power arm,
• e. control means interconnecting the power arm and crank arm for rotating the crank arm and drive member, and for accelerating the power arm ahead of the crank arm during one portion of the crank arm cycle and decelerating the power arm behind the crank arm during another portion of the crank arm cycle, and
• f. the control means including:
• 1. a cam surface provided on one of the arms, and
• 2. a cam element having a shaft rotatively mounted on the other of the arms and having a cam follower spaced from the shaft and engaging the cam surface.

A drive assembly for physically propelled vehicle comprising:

• a. a drive member rotatively mounted on a drive axis,
• b. a crank arm operatively connected to the drive member for rotating the drive member,
• c. a power arm rotatively mounted on the drive axis for relative angular movement between the power arm and crank arm,
• d. a pedal means operatively connected to the power arm for rotating the power arm,
• e. control means interconnecting the power arm and crank arm for rotating the crank arm and drive member, the control means including:
• 1. a cam slot in the power arm, and
• 2. a cam element having a shaft rotatively mounted in the crank arm, a cam follower spaced from the shaft and received in the cam slot, and a link between the shaft and cam follower,
• f. the pedal means includes:
• 1. a sun gear fixedly mounted on the drive axis, and a planet gear meshing with and rotatable about the sun gear and connected to the cam shaft of the cam element to cause relative rotation of the cam element and crank arm during rotation of the crank arm and power arm for selectively moving the power arm ahead of and behind the crank arm as the cam follower rides on the cam surface.