Patent ID: 6568513
Filing Date: 2003-05-27
Classification: F16D

Abstract:
An adjustment arrangement for a drum brake having a hydraulic actuator that engages a first web of a first brake shoe and a second web of a second brake shoe, said hydraulic actuator receiving a hydraulic input for developing an actuation force to move said first and second brake shoes from a rest position into engagement with a rotatable member to effect a brake application, an extendible member that is connected to said first web and said second web and is extendable to define a running clearance in a rest position between said first and second brake shoes and said rotatable member, a lever arm that is mounted on said first web and engages said extendable member and a resilient member that extends between said lever to said second web to urge said first and second webs into engagement with said hydraulic actuator, said lever arm pivoting with respect to said first web when said first web moves through said running clearance and when said running clearance reaches a predetermined maximum width pivots to provide for extension of said extendible member and establish a minimum width for said running clearance, said adjustment arrangement being characterized by said first web has a first segment that is connected to a second segment through an integral projection, said integral projection functioning as a fulcrum for said second segment to define a cantilever arm with a first end and a second end, first end being free to move while said second end engages an anchor for said first and second brake shoes, said first segment having a first engagement surface that is connected to said hydraulic actuator while said first end of said cantilever arm defines a second engagement surface that is connected to said extendible member, said first engagement surface receiving said actuation force from said hydraulic actuator for moving said first brake shoe through said running clearance and into engagement with said rotatable member to effect said brake application while movement of said first engagement surface in response to the actuation force is also communicated to said second engagement surface through said cantilever arm and is limited as a function of the location with respect to the second end of said cantilever arm and the resiliency of said projection.