Method and apparatus for establishing and maintaining a selected tension on uncoiling wire

An apparatus for applying and maintaining a predetermined tension on a fine, metallic wire being uncoiled from a spool of wire, including:

• a base,
• a spool-receiving, tubular column mounted on said base and extending above said spool of wire,
• a member mounted for rotation on a rod extending into the top of the tubular column,
• said member having at least one outwardly-extending arm with an opening in said arm though which said wire passes,
• a sleeve positioned in the upper end of said tubular column to receive said rod and having a surface projecting above said tubular column to engage and support said member having at least one arm,
• a nut threaded to the top of said rod and having a braking surface facing said member having at least one arm,
• a coiled spring positioned in said tubular column and biasing said rod to move the braking surface of said nut away from said member having at least one arm,
• a cable connected to said rod to pull said rod directly against the upward force exerted by said coiled spring, and
• means to reduce the pulling force of said cable against said rod as the pulling force exerted against said fine wire to uncoil it increases, said means including:
• a pulley for guiding said fine wire during uncoiling,
• a pivotally-mounted arm cantileverly supporting said pulley located at the distal end of said arm,
• the opposite end of said arm operatively connected to said cable to reduce the pulling force of said cable against said rod as said arm pivots due to an increasing pulling force on said pulley exerted by said wire.

An apparatus for establishing and maintaining a selected tension on a fine wire being uncoiled from a spool of such wire by a pulling force, said apparatus including:

• a disk mounted for rotation at one end of said spool of wire,
• said disk having at least one outwardly-extending arm with an opening in said arm through which said wire passes,
• means to provide a braking resistance against rotation of said disk proportional to the pulling force expected to be applied to the uncoiling wire, and
• means to continuously adjust said braking resistance applied to said disk as the pulling force applied to said uncoiling wire varies.