| 摘要 |
A self-compensating tension control device for regulating the withdrawal of filamentary material from a spool includes a fixed support that maintains an inverted cam surface and a spindle assembly rotatably carrying the spool. A tension force applied to the filamentary material, in opposition to a biasing force, moves the spindle assembly linearly in relation to the fixed support. A braking mechanism includes a brake drum rotatable with the spindle assembly, a friction band adapted to engage the brake drum and a rocker arm that engages the cam surface. When the tension force applied to the filamentary material is reduced and unable to overcome the biasing force, the cam roller engages the cam surface and causes the friction band to generate a braking force on the brake drum. Withdrawal of the filamentary material at a regular rate occurs when the biasing force is balanced with the tension force. |
