| 摘要 |
An improved brake drive apparatus having a brake surface formed in a portion thereof and a brake assembly interposed generally between and connected to an input drive assembly and to an output member, the output member being rotatingly driven via the input drive assembly in the driving mode of the brake assembly and the brake assembly being positioned in the braking mode for preventing rotation of the output member in response to a torque applied at the output member. The brake assembly includes: a brake ring connected to and rotatingly driven via the input drive assembly; a first and a second brake shoe element, each having a portion engageable via a portion of the brake ring; a driven cam connected to the output member and disposed generally between the first and second brake shoe elements; and at least one brake roller disposed generally between the brake shoe elements and the driven cam. When the brake ring is rotatingly driven via the input drive assembly, the brake shoe elements are rotatingly driven via the brake ring and the driven cam is rotatingly driven following the rotation of the brake shoe elements as a result of the engagement between the driven cam and the brake shoe elements provided by the brake rollers, the output member being rotatingly driven via the driven cam as a result of the connection therebetween. When a torque is applied at the output member, the driven cam applies a force on the brake shoe elements via the brake rollers causing the brake shoe elements to be moved into braking engagement with the brake surface in the housing preventing the rotation of the output member even in those instances where the input drive assembly continues to be rotatingly driven. |
