Patent ID: 6460659
Filing Date: 2002-10-08
Classification: F16D

Abstract:
A machine having a housing, a rotatable torque transmitting member in said housing and a source of fluid pressure, said machine comprising:a friction coupling including: a reaction surface on said housing transverse to the axis of said torque transmitting member; a friction disc connected coaxially to and for rotation with said torque transmitting member; said friction disc including abradable friction material on its axially opposite sides; a fluid operated brake piston mounted within said housing in coaxial relation to said torque transmitting member for axial movement in a brake applying direction, in which said brake piston is moved into engagement with said friction disc to capture it against said reaction surface and for axial movement in a brake retracted direction in which said brake piston moves away from said friction disc; and a brake wear indicator operatively associated with said brake piston providing a visual indication that excessive wear of said friction material has occurred when said brake piston moves in said brake applying direction a predetermined distance, the brake wear indicator including: a pin element mounted within said housing for axial movement in the direction of said axis of said torque transmitting member, said pin element including an abutment surface near one of its axially opposite ends engageable with said brake piston when said brake piston is moved in said brake applying direction; and a window in said housing permitting an approximate right angle view of the other axial end of said pin element, the position of said other axial end of said pin element in said window being indicative of the wear condition of said friction coupling.