| 摘要 |
A weight-saving crank arm having two spaced-apart connecting members extending between the pedal eye and the hub of the crank arm. The connecting members are preferably arranged at a relatively large angle with respect to each other so as to transmit the wheel-turning torque through a cross section having a large moment of inertia Iz, where z-axis is the axis transverse to the longitudinal axis of the crank arm. So arranged, one connecting member will carry mostly tensile forces and the other connecting member will carry mostly compressive forces during use. Due to this separation of load-carrying functions, structural properties such as, for example, stiffness and strength of the connecting members can be advantageously optimized. For example, each of the connecting members can be precisely and selectively dimensioned such that the tension-carrying member may have a thicker cross section than that of the compression-carrying member since the compressive strength of a material far exceeds the tensile strength of the same material.
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