Rotary shaft brake

A self-regulating brake assembly for controllably releasing reactive torque stored as torsion in an axially rotatable a shaft which is driven in a forward direction and rotates in a reverse direction during release of the torsion stored therein, the brake assembly comprising:

• a rotary member for rigidly connecting and axially rotating with a shaft;
• a fluid actuated brake mechanism for retarding rotation of the rotary member and consequently the shaft upon pressure build up in the brake mechanism, the break mechanism having a caliper;
• a bi-directional pump or conveying fluid from a reservoir, the pump being driven by rotation of the shaft;
• a control manifold for circulating the fluid from the pump through the brake mechanism and the caliper and back to the reservoir without pressure build up, the circulation of the fluid preventing accumulation of gas in the brake mechanism and the caliper, when the shaft is rotating in a forward direction an for controlling the flow of fluid through the brake mechanism during reverse rotation of the shaft for building up pressure in the brake mechanism to activate the brake mechanism and caliper and retard rotation of the shaft during reverse rotation of the shaft.

A self-regulating brake assembly for controllably releasing torsion due to reactive torque stored in a shaft for a down hole submersible pump in a well, which shaft is driven for rotation in a pump operating direction during operation of the pump and rotates in a reverse direction during release of the stored torsion, the brake assembly comprising:

• a rotary member for rigidly connecting with shaft for rotation therewith;
• a hydraulic fluid acruated brake mechanism for retarding rotation of the rotary member and consequently the shaft upon pressure build up in the brake mechanism, the break mechanism having a caliper;
• a bi-directional pump for conveying hydraulic fluid from a reservoir during rotation of the shaft;
• a control manifold for circulating the hydraulic fluid from the pump through the brake mechanism and caliper and back to the reservoir without pressure build up, the circulation of the hydraulic fluid preventing the accumulation of gas in the brake mechanism and caliper and for flushing the brake mechanism caliper when the shaft is rotating in the pump operating direction and for controlling the flow of the fluid through the brake mechanism to build up pressure in the brake mechanism to activate the brake mechanism when the shaft is rotating in the reverse direction.