Brake system for mining conveyor

A brake apparatus for use with a rotatable mechanical load, said brake apparatus comprising:

• a longitudinal shaft;
• a stationary housing rotatably supporting said longitudinal shaft such that a first end portion extends for coupling to said mechanical load;
• a rotating plate carrier fixedly secured to said longitudinal shaft, said rotating plate carrier having a cylindrical portion concentric with said longitudinal shaft maintaining a first plurality of annular brake plates in axial displacement along said longitudinal shaft;
• a stationary plate carrier integral with said stationary housing and having said longitudinal shaft extending completely therethrough, said stationary plate carrier being positioned radially between said longitudinal shaft and said cylindrical portion of said rotating plate carrier, said stationary plate carrier maintaining a second plurality of annular brake plates in axial displacement along said longitudinal shaft, said first plurality of annular brake plates and said second plurality of annular brake plates being interleaved to form a braking assembly;
• an actuating mechanism for selectively varying frictional engagement of said first plurality of annular brake plates and said second plurality of annular brake plates to control a braking torque applied to said longitudinal shaft, wherein said actuating mechanism includes:
• an annular piston juxtaposed to said braking assembly and being axially moveable in a direction away from said braking assembly by introduction of actuation fluid into a fluid chamber adjacent said annular piston, said annular piston thereby selectively lessening the braking torque applied to said longitudinal shaft;
• and
• a biasing mechanism for causing frictional engagement of said first plurality of annular brake plates and said second plurality of annular brake plates in the absence of actuation of said annular piston to apply a predetermined braking torque to said longitudinal shaft,
• wherein the actuation fluid is introduced into said fluid chamber through a fluid inlet located such that said annular piston will be urged by said biasing mechanism when wear of said braking assembly has exceeded a preselected threshold to an axial position wherein said actuation fluid cannot be introduced into said fluid chamber;
• and
• at least one coolant passage defined by said stationary plate carrier in communication with said first and said second plurality of annular brake plates such that coolant fluid may flow into said passage and then pass between respective of said annular brakes plates for cooling same.

A brake system for use with a rotatable mechanical load, said brake system comprising:

• a brake unit having a rotatable shaft operatively coupled to said mechanical load, said brake unit having a braking mechanism biased to normally apply a predetermined braking torque to said rotatable shaft and being controllably releasable to vary the braking torque applied to said shaft;
• said braking mechanism including a brake plate assembly having a first plurality of brake plates rotatable with said rotatable shaft and a second plurality of non-rotatable brake plates, said first plurality of brake plates and said second plurality of brake plates being interleaved;
• said braking mechanism further including an annular piston defining a fluid chamber adjacent thereto, and a biasing mechanism for biasing said piston against said brake plate assembly causing said predetermined braking torque to normally be applied to said rotatable shaft, said piston being moveable in a direction away from said brake plate assembly by introduction of an actuation fluid into said fluid chamber for selectively lessening the braking torque applied to said shaft;
• wherein the actuation fluid is introduced into said fluid chamber through a fluid inlet located such that, when wear of said brake plate assembly has exceeded a preselected threshold, said piston will be urged by said biasing mechanism to a position that substantially prevents said fluid chamber from receiving said actuation fluid thereby maintaining said piston against said brake plate assembly.

A brake apparatus for use with a rotatable mechanical load, said brake apparatus comprising:

• a longitudinal shaft;
• a stationary housing rotatably supporting said longitudinal shaft such that one end of said shaft extends for coupling to said mechanical load;
• a braking assembly having at least one first frictional member fixedly connected to said longitudinal shaft and at least one second frictional member fixedly connected to said stationary housing, said first frictional member and said second frictional member engageable to apply a braking torque to said longitudinal shaft;
• an annular piston juxtaposed to said braking assembly and being axially moveable in a direction away from said braking assembly by introduction of actuation fluid into a fluid chamber adjacent said annular piston, said annular piston thereby selectively lessening the braking torque applied to said longitudinal shaft;
• and
• a biasing mechanism for causing frictional engagement of said first frictional member and said second frictional member in the absence of actuation of said annular piston to apply a predetermined braking torque to said longitudinal shaft, said biasing mechanism comprising a plurality of removable spring assemblies radially displaced about said longitudinal shaft and located to urge said annular piston toward said braking assembly, each of said removable spring assemblies including a longitudinal guide rod, at least one helical spring coaxially mounted about said guide rod, and first and second cup members disposed over opposite axial ends of said helical spring, one of said first and second cup members defining a hole in an end thereof to permit said guide rod to pass therethrough as said at least one helical spring is compressed.