Abstract: An electromagnetic disk brake is compact, self-sealing, self-contained, has relatively few components, and is relatively easy to fabricate and to install when compared to traditional electromagnetic disk brakes. Self-containment and self-sealing are achieved by providing a skirt on the field cup that extends over the remaining moving components of the brake and that is attached, preferably by a press-fit, to a reaction plate at the inner end of the brake. The need for stand-offs to set the air gap of the brake can be eliminated by suitable control of the press-fitting of the field cup onto the reaction plate. For electric motor braking applications, the reaction plate can form the endbell of the electric motor, thereby combining the endbell, mounting plate and reaction plate in a single plate. Simplicity and ease of assembly of a spring-applied brake are enhanced further by employing a single compression spring at the center of the brake rather than a plurality of peripherally-spaced springs.

Abstract: A power-off electromechanical brake employs a friction disk compressed between a ferromagnetic clapper plate and a pressure plate. An electromagnet may pull the clapper plate away from the friction disk or the pressure plate and clapper plate may be separated by free floating spacer elements held within a rotating race positioned between the clapper plate and the pressure plate. In a first mode, cavities in the clapper plate receive spacer elements held within the race and the friction disk is compressed. In a manual release mode, the spacer elements no longer engage with the cavities and separate the pressure plate and clapper plate.