US Patent 9790720 Torque element retention system

One aspect is a torque element retention system with a housing having an opening. A torque assembly has a shaft and a torque element stacked along the shaft and is configured substantially within the opening of the housing. The torque element has an arm portion and a foot portion and the opening has an arm opening section configured to receive the arm portion of the torque element and a foot retention section configured to receive the foot portion of the torque element. The torque element retention system has a system axis through the center of the shaft and extending through the foot retention section. The at least one of the first and second foot end portions of the foot retention section includes first and second non-parallel segments having no normal length to chord length ratio greater than 0.5.