Abstract: A brake assembly (10) for selectively starting and stopping rotation of a shaft (12) journaled in a frame (14) of a motor comprises an end plate (16) mounted to the motor frame, the end plate (16) being formed with mounting slots (40) formed axially therein. Friction discs (26, 26a) are secured to the shaft (12) for rotation therewith about the longitudinal axis of the shaft (12) and pressure plates (36, 36a, 36b) are non-rotatably mounted in the mounting slots (40) of the end plates (16) and axially movable toward and away from the friction discs (26, 26a).

Abstract: A motor brake mechanism (10) includes retaining structure (46) permitting removal and replacement of friction discs (16, 18) without disassembling the brake mechanism. When the brake mechanism is detached from the motor, removal of a single bolt (46) permits radial removal and replacement of the friction discs. Minimizing of brake drag is enabled by adding low force compression springs (162, 164, 166, 168, 170, 172) without otherwise modifying the structure which prevents rotation of the pressure plates (38, 40) relative to the end plate (28) of the brake mechanism (10), wherein a first set of studs (42, 44, 46) provide both functions of non-rotatably mounting the pressure plates (38, 40) to the end plate (28) and mounting the low force compression springs, all separate from another set of studs (70, 72) mounting the brake lever (68) to the end plate (28).

Abstract: A brake mechanism is disclosed wherein a support lever is pivoted at a pivot end to a stationary bearing plate and is urged by a plurality of springs, which engage the support lever radially inwardly from its pivot end, toward the end plate to effect clamping of a rotatable friction disc between the end plate and a brake shoe disposed near the pivot end of the support lever. A solenoid has a plunger pivotally connected directly to a bracket end of the support lever adapted to overcome the forces applied by the springs and release the brake when the solenoid is energized. The springs apply pressure in close proximity to the pivot point and with the solenoid being disposed at the remote free end of the support lever, there are achieved greater mechanical advantages without the need for complicated linkage assemblies. The arrangement of parts is such that the solenoid mechanical advantage is substantially 7 to 1, while the spring-set mechanical advantage is approximately 7 1/2 to 1.