Warp let-off device for loom

Abstract

A warp let-off device for a loom includes a drive unit having a rotational drive source and a transmission which transmits rotation of the drive source to a warp beam, the drive unit rotating the warp beam in an unwinding direction while applying a braking force against a warp tension to the warp beam; and a brake unit which applies a braking force to the warp beam separately from the braking force applied by the drive unit.

1 . A warp let-off device for a loom, comprising: 
 a drive unit including a rotational drive source and a transmission which transmits rotation of the drive source to a warp beam, the drive unit rotating the warp beam in an unwinding direction while applying a braking force against a warp tension to the warp beam; and    a brake unit which applies a braking force to the warp beam separately from the braking force applied by the drive unit.    
   
   
       2 . The warp let-off device for the loom according to  claim 1 , wherein the warp let-off device can also rotate the warp beam in a winding direction opposite to the unwinding direction, and wherein the brake unit is provided with braking-force reducing means for reducing the braking force applied by the brake unit when the warp beam rotates in the winding direction.  
   
   
       3 . The warp let-off device for the loom according to  claim 2 , wherein the braking-force reducing means comprises a one-way rotation transmission interposed between the brake unit and a rotating shaft of the warp beam.  
   
   
       4 . The warp let-off device for the loom according to  claim 2 , wherein the braking-force reducing means comprises an actuator which reduces a contact pressure between a circular brake plate and brake discs, the circular brake plate being integrated with a brake shaft.