Outer plates have a doughnut-like disk shape and are attached to the inner circumferential surface of a case member. On the other hand, inner plates have a substantially arc shape and are swingably supported about a position at a distance from the center of rotation of a shaft. The inner plates are held at a first position, at which the interlocking area between the outer plates and the inner plates is small, by a tension coil spring when the relative rotational speed between the case member and the shaft is small, and, when the relative rotational speed between the case member and the shaft exceeds a predetermined value are pivotally moved toward the outer plates by the shearing force of a viscous fluid and held at a second position at which the interlocking area between the movable plates and the first plates is large.

A centrifugal brake mechanism for a controlled descent device, and a drum device employing it. The brake mechanism comprises a circular wheel configured and operable to rotate about an axis of rotation, an axle extending along and rotatable about the axis inside a central cavity of the wheel and having two or more parallel shaft rods extending inside the cavity substantially perpendicular to the axis of rotation, a gear system for transferring rotations of the wheel into counter-rotations of the axle, one or more brake elements each having two or more pass-through bores for slidably mounting over the two or more parallel shaft rods, two or more springs mounted over the parallel shaft rods between the brake element and the axle, and a friction enhancement mechanism for increasing friction forces between the brake elements and the inner wall the wheel responsive to increase in angular velocity of the wheel.

The present invention relates to an unpowered braking device using centrifugal force. The present invention may comprise: a housing; a brake drum installed inside the housing; a plurality of braking links rotatably installed on a rotating shaft of the housing and connected such that both ends thereof can expand and contract by means of centrifugal force; brake rollers provided on both ends of the braking links, respectively, such that, when the braking links expand, the brake rollers are forced against the inner walls of the brake drums and thereby generate braking force/torque; and an elastic member for providing elastic force such that both ends of the braking links, which have expanded, can contract.

Winches with axially aligned, mechanically actuated brakes, and associated systems and methods are disclosed. A representative winch includes a cable drum rotatable in a winding direction and an unwinding direction, a drive motor, a drive shaft coupled to the drive motor and rotatable about a shaft axis, a gear train coupled to the drive shaft and the cable drum, and a mechanically actuated brake. The brake can include a first element coupled to the drive shaft and rotatable about the shaft axis, a second element coupled to the cable drum and rotatable about the shaft axis, and a friction element positioned between the first and second elements and rotatable about the shaft axis. At least one of the first and second elements can be movable toward and away from the other between an engaged position with the friction element clamped between the first and second elements, and a disengaged position with the friction element unclamped.

A method and a safety brake for a lifting device, wherein a solenoid or another electromechanical actuator is used to actuate a pawl, where the position of the pawl is monitored via at least two switches or sensors, where the lowering motion of the load or the lifting device is monitored and the safety brake is triggered in the event of a fault via a safety-oriented controller and at least one sensor, where the solenoid or the pawl is arranged such that, via spring force and/or gravity, the pawl is brought into engagement when the actuator, for example, the solenoid, is deenergized such that it is possible to exactly define and monitor the limit speed and, by using the two sensors, it is also possible to monitor the function and the motion of the pawl and to detect undesired operating states.

A rotation velocity adjusting module includes a fixed axle, a rotating component and a rotation velocity adjusting mechanism. The rotating component is pivoted to the fixed axle. The rotation velocity adjusting mechanism includes a driven component, a driving component and a contact component. The driven component is rotatably connected to the rotating component. The driving component and the contact component are disposed on the driven component. When a rotation velocity of the rotating component reaches a threshold value, the driving component drives the driven component to rotate by the change of centrifugal force, so as to switch states of the contact component.

An actuator drive, for blinds, roller shutters and the like, has a drive motor and a centrifugal brake. A rotational disk is coupled to a drive shaft of the drive motor via a shaft flange. Two centrifugal shoes are smoothly guided in the rotational disk. In the unpowered state, brake shoes of the centrifugal shoes engage, frictionally or in a positive-locking way on an outer surface of a friction ring fixed to the motor housing. Upon starting of the drive motor, the brake shoes release the friction ring. The radial displacement of the brake shoes is maintained until the drive motor comes to a stop, wherein the brake shoes 8 are drawn radially inward by spring elements and function again as a locking mechanism. The spring elements are pretensioned such that the brake shoes effect a sufficient retaining torque.

Described herein is a system, method of use and Self Retracting Lifeline (SRL) apparatus using a system that governs a dynamic response between members causing a halt in relative motion between the members. Magnetic interactions, eddy current drag forces and centrifugal and/or inertial forces may provide various mechanisms of governing movement.

A centrifugally triggered brake mechanism is used to halt a rotating assembly. The brake mechanism includes a braking surface, a brake shoe, and a rotating centrifugal trigger. Upon attaining a selected rotational speed the trigger releases the brake pad to engage the drum. The mechanism may be useful for instance in providing backup overspeed protection for wind turbines.

Systems, methods, and devices are provided to generate a stable supply of electrical power in a drill string. In one example, a downhole turbine generator includes a turbine, a speed governor, and an alternator. The turbine may transform hydraulic power of a first fluid medium into rotational power of a rotating shaft. The speed governor may reduce the rotational power of the rotating shaft in a variable amount that depends on the speed of the rotating shaft. Specifically, weighted arms may shear a second fluid medium more when the speed is higher and less when the speed is lower. The shearing of the second fluid medium may generate a countervailing torque on the rotating shaft to reduce the rotational power of the rotating shaft. The alternator then may produce a generally stable supply of electrical power from the rotational power of the rotating shaft.