The entire power assisting device is composed of a central electric motor, controller, transmission ratio gear, spoke-type torque sensor, cadence sensor and other components. Strain gauge type torque transducer manufacturing process is adopted in spoke-structure torque sensor with the spoke-type elastomeric hub fixed to the crankset and the rim fixed to the middle axle, thus having high stability, high reliability, high sensitivity and long service life.
This device requires no transformation of the bicycle frame and bottom bracket shell, and is thus suitable for any standard bicycle.
Put the tubular pipe with middle axle through the bottom bracket shell and fasten with nuts, and then fasten the casing onto the front oblique bar of the frame with assorted pendant.
Fix the tension—torque sensor above the bottom fork near the chain wheel (flywheel), so that the tension—torque sensor keeps parallel to the movement direction of chain and the chain above the bottom fork is in V shape to the chain in crankset.
To avoid adjustment of the chain length (tensioning), please mount assorted chain tension gear provided by us at lower half circle of the chain, i.e. below the bottom fork and near the chain wheel.
Since chain transmission exists between chain wheel (flywheel) and crankset, the chain will be in “V” shape when mounting torque sensor between them. When riding the bicycle, the “V” shape chain will be tensioned into straight shape and the chain tensioning will change synchronously along with the treading force treading force with linearity signal output.. The tension—torque sensor mounted above the chain will detect the treading force during riding via the change of chain tension at any time and any place, and convert such force into electric signals to the intelligent controller.
Crank and crankset are directly installed and fixed on spoke-structure elastomer. A resistance strain gauge is pasted on the spoke and middle axle is directly put into the square cone hole on the crank head and fastened with screws. During riding, the opposite force direction between crankset and crank will make the elastomeric spoke in the middle deformed and generate electric signal output.
With compact structure, simple and convenient installation and use and no need to remove the middle axle, crankset crank-type torque sensor can be mounted by dismounting the original crankset crank on the bicycle.
The torque sensor in this product falls into two models of wire transmission and wireless transmission on output signal. The wire transmission type can be mounted by fastening the crank-type torque sensor and static collector tray and inserting the torque signal line at the controller end into the output socket of the static collector tray.
The wireless transmission type can be used by mounting and fixing the static collector tray at the crankset side of the bottom bracket shell, connecting the data signal line on the static collector tray with corresponding interface on the controller and then inserting the crank torque sensor into the middle axle and fastening with screws