Patent ID: 7836813

Claim:
A self-locking braking device for rotary shafts comprising: a support body for a rotatably supported drive shaft, the drive shaft being operatively connectable to an external load; braking means operatable to lock, respectively to release the rotation of the drive shaft, the braking means comprising a braking member rotating with the drive shaft, the braking member being interposed between a first clutch member secured to the support body, and a second clutch member carried by an axially movable support element, the support element of the second clutch member being connected to the piston of a pneumatic cylinder; and biasing spring means between said support element for the second clutch member and the support body for the drive shaft, said biasing spring means being shaped and arranged to lock the braking member and keep it locked between said clutch members, wherein said braking member is in the form of a rigid disk conformed with friction surfaces on both sides; and wherein said braking disk is slidingly supported in an axial direction by the drive shaft, in a floating condition between the two clutch members, wherein elastically yielding spacing means are interposed between the braking member and the support body, on the side of the first clutch member.