초록 ▼

An automatic speed range shifter for bicycles is disclosed which produces a downshift when a predetermined pedal force is exceeded and which produces an upshift when a predetermined pedal rotational speed is exceeded. A pedal force sensor includes a strain gage element on an arm supporting an idler

An automatic speed range shifter for bicycles is disclosed which produces a downshift when a predetermined pedal force is exceeded and which produces an upshift when a predetermined pedal rotational speed is exceeded. A pedal force sensor includes a strain gage element on an arm supporting an idler sprocket for the chain. A pedal rotational speed sensor includes a magnet/coil coacting with the pedal crank. A microcomputer receives inputs from the force and speed sensors and produces control signals for the automatic shifter. The automatic shifter includes a front shifter actuator including a reversible electrical servo motor which is coupled by a cable with the front derailleur. It also includes a rear shifter actuator with a reversible servo motor which is coupled by a cable with the rear derailleur.

대표청구항 ▼

The method of operating a velocipede of the type comprising a traction wheel, a manually actuated pedal crank, a drive train between the traction wheel and the pedal crank, a speed range changing power transmission operatively connected in the drive train and a control member for upshifting and down

The method of operating a velocipede of the type comprising a traction wheel, a manually actuated pedal crank, a drive train between the traction wheel and the pedal crank, a speed range changing power transmission operatively connected in the drive train and a control member for upshifting and downshifting the speed range of the transmission, said method comprising the steps of: measuring the pedal crank speed and pedal crank force, pedalling the velocipede in a selected speed range, producing a first control signal when the time average value of rotational speed of the pedal crank increases to a predetermined value, initiating actuation of the control member to upshift the transmission when the first control signal is produced, producing a second control signal when the time average value of pedal crank force increases to a predetermined value, and initiating actuation of the control member to downshift the transmission when the second control signal is produced. An automatic speed range shifter for a velocipede having a traction wheel, a manually actuated pedal crank, a drive train between the pedal crank and the traction wheel and a ratio-changing transmission operatively connected in said drive train and a control member for upshifting and downshifting the speed range of the transmission, said shifter comprising: means for measuring the pedal crank speed and pedal crank force, means for producing a first control signal when the time average value of rotational speed of the pedal crank increases to a predetermined value, means for initiating actuation of the control member to upshift the transmission when the first control signal is produced, means for producing a second control signal when the time average value of pedal force increases to a predetermined value, and means for initiating actuation of the control member to downshift the transmission when the second control signal is produced.