Cam-operated, spot brake structure

Claim 1

A BRAKE FOR CONTROLLING A ROTATABLE MEMBER COMPRISING FRICTION DISC MEANS AXIALLY SHIFTABLY MOUNTABLE ON AND ROTATABLE WITH THE ROTATABLE MEMBER TO BE CONTROLLED, A FIXED ONE PIECE FRAME MEMBER OF LIMITED CIRCUMFERENTIAL EXTENT AND HAVING A GENERALLY C-SHAPED CROSS SECTION INCLUDING OPPOSED FIRST AND SECOND FLANGE PORTIONS OVERLAPPING LIMITED CIRCUMFERENTIAL SECTIONS OF OPPOSITE SIDES OF SAID DISC MEANS, SAID FIRST FLANGE PORTION HAVING MEANS PRESENTING A FLAT FRICTION SURFACE OF LIMITED CIRCUMFERENTIAL EXTENT PARALLEL TO SAID DISC MEANS, SHOE MEANS SHIFTABLY DISPOSED BETWEEN SAID SECOND FLANGE PORTION AND SAID DISC MEANS, WEDGING MEANS DISPOSED BETWEEN SAID SHOE MEANS AND SAID SECOND FLANGE PORTION FOR SHIFTING THE SHOE MEANS TOWARD SAID DISC MEANS AND CLAMPING THE DISC MEANS BETWEEN THE SHOE MEANS AND SAID SURFACE WHEN THE BRAKE IS ENERGIZED, SAID WEDGE MEANS COMPRISING A PAIR OF ABUTTING ANTI-FRICTION BEARING ELEMENTS AND A CAGE MEMBER RETAINING SAID BEARING ELEMENTS, SAID SECOND FLANGE PORTION INCLUDING A STRAIGHT BEARING GROOVE SURFACE PARALLEL TO SAID DISC MEANS AND SAID FRICTION SURFACE AND ENGAGEABLE WITH ONE OF SAID BEARING ELEMENTS, SAID SHOE MEANS INCLUDING A SECOND BEARING SURFACE INCLINED WITH RESPECT TO SAID FIRST MEMTIONED BEARING GROOVE SURFACE AND ENGAGING THE OTHER OF SAID BEARING ELEMENTS, AND MEANS CONNECTED WITH SAID CAGE MEMBER FOR EXERTING AN ACTUATING AND SHIFTING FORCE ON SAID CAGE MEMBER AND BEARING ELEMENTS IN A DIRECTION EXTENDING PARALLEL TO SAID FIRST MENTIONED BEARING GROOVE SURFACE.