Fluid operated modular clutch-brake device

Abstract

A clutch-brake device having a housing, a shaft rotationally mounted therethrough, modular coupling units rigidly coupled to the shaft at either side of the housing, and an adapter which allows a single modular unit to be utilized interchangeably in either a clutch or a brake configuration. Each modular unit has a coupling member carrying an annular friction ring. The coupling member is rotationally connected to and spaced apart from a resilient disk defining a vacuum chamber therebetween. The resilient disk is rigidly attached to the modular unit and may be tapered towards the outer edge. The modular unit may also have several shims predisposed between the resilient disk and the coupling member which can be periodically removed to maintain the gap between the resilient disk and the annular friction ring within a preferred range. The device may have a microprocessor controlled high speed switch for controlling electromagnets which regulate engagement of the resilient disks. The microprocessor may utilize current controlled pulse width modulation and may regulate the energy applied to the electromagnets at a first energizing threshold power level and a second holding threshold power level. Additionally, the microprocessor may briefly reverse the polarity of the electromagnets to repel vacuum blocking discs associated with therewith. The microprocessor may also provide a coast time during which both the brake and the clutch are contemporaneously disengaged. The vacuum blocking discs which are typically round may have four straight edges machined slightly therein to form a square with rounded corners.