Symmetric Master Cylinder Lever for a Hydraulic Disc Brake II

Abstract

A master cylinder lever for a hydraulic disc brake comprises a lever pivotally connected to a master cylinder housing and a bar clamp attached to the master cylinder housing for attaching the master cylinder housing to a bicycle handle bar along a longitudinal clamp axis. A cylinder wall is associated with the master cylinder housing, the cylinder wall comprising a cylinder interior and a cylinder exterior extending axially of a cylinder axis. A reservoir is associated with the master cylinder housing and is in fluid communication with the cylinder interior through a port in the cylinder wall. The reservoir comprises only a radial portion of the cylinder exterior. A piston within the cylinder has a seal operatively associated therewith. The piston is movable between first and second cylinder ends along a cylinder axis with the seal preventing flow of hydraulic fluid from the reservoir to the second cylinder end upon the seal advancing axially past the port as the piston moves from the first toward the second cylinder end. The lever, the bar clamp, the master cylinder housing and the reservoir are configured to provide a symmetric master cylinder about a plane defined by the longitudinal clamp axis and cylinder axis, whereby the master cylinder lever may be operatively disposed on either a right or left portion of a handlebar of a bicycle without effecting operation of the master cylinder lever by a user.

1 . A master cylinder lever for a bicycle hydraulic disc brake comprising: 
 a lever pivotally connected to a master cylinder housing;    a bar clamp attached to the master cylinder for attaching the master cylinder housing to a bicycle handlebar along a longitudinal clamp axis;    a cylinder wall associated with the master cylinder housing, the cylinder wall comprising a cylinder interior and a cylinder exterior extending axially of a cylinder axis;    a reservoir associated with the master cylinder housing in fluid communication with the cylinder interior through a port in the cylinder wall, the reservoir comprising only a radial portion of the cylinder exterior;    a piston within the cylinder having a seal operatively associated therewith, the piston being moveable between first and second cylinder ends along a cylinder axis, the seal preventing flow of hydraulic fluid from the reservoir to the second cylinder end upon the seal advancing axially past the port as the piston moves from the first toward the second cylinder end; and    the lever, the bar clamp, master cylinder housing and the reservoir being configured to provide a symmetric master cylinder lever about a plane defined by the longitudinal clamp axis and the cylinder axis, whereby the master cylinder lever may be operatively disposed on either a right or left portion of a handle bar of a bicycle without effecting operation of the master cylinder lever by a user.