US 6,804,961 B2 · Master cylinder lever for a hydraulic disk brake having on the fly dead-band adjustment

Abstract

A master cylinder for a bicycle hydraulic disc brake includes a cylinder having a port in fluid communication with a hydraulic fluid reservoir. The port opens to the cylinder between first and second ends of the cylinder. A piston within the cylinder is movable between a select starting position with the seal between the first end of the cylinder and the port opening with the piston a select distance from the port opening and a pressurized position with the seal between the port opening and the second end of the cylinder. A dead-band adjustment structure is operatively associated with the piston for moving the select starting position to adjust the select distance between the port opening and the seal. A lever is pivotably attached to the housing and is operatively associated with the piston to move the piston between the select starting position and the pressurized position as the lever is pivoted between a rest position and a fully-actuated position. A compensating structure operatively associated with the dead-band adjustment structure and the lever maintains the lever in a select rest position as the dead-band adjustment structure is actuated to move the select starting position.

Claims17

Dependent claims

A master cylinder for a bicycle hydraulic disc brake, the master cylinder comprising:

a housing defining a cylinder, the cylinder having a first and a second end;
a hydraulic fluid reservoir;
a port between the hydraulic fluid reservoir and the cylinder providing fluid communication between the hydraulic fluid reservoir and the cylinder, the port having a port opening located between the first and second ends of the cylinder;
a piston received in the cylinder having a radial seal, the piston being movable between a select starting position with the seal between the first end and the port opening with the seal a select distance from the port opening and a pressurized position with the seal between the port opening and the second end, the radial seal preventing fluid flow between the cylinder and the reservoir when positioned between the port opening and the second end to pressurize the second end;
dead band adjustment means operatively associated with the piston for moving the select starting position to adjust the select distance between the port opening and the seal;
a lever pivotably attached to the housing, the lever being operatively associated with the piston to move the piston between the select starting position and the pressurized position as the lever is pivoted between a rest position and a fully actuated position;
and
compensating means operatively associated with the dead band adjustment means and the lever to maintain the lever in a select rest position as the dead band adjustment means is actuated to move the select starting position.

5 more elements

A master cylinder lever for a bicycle hydraulic disc brake, the master cylinder lever comprising:

a housing defining a cylinder, the cylinder having a first end and a second end along a cylinder axis;
a hydraulic fluid reservoir;
a port between the hydraulic fluid reservoir and the cylinder providing fluid flow therebetween, the port having a port opening located between the first and second ends of the cylinder;
a piston received in the cylinder, the piston having a seal and being movable between a select starting position with the seal between the port opening and the first end of the cylinder and a pressurized position with the seal between the port opening and the second end, the seal preventing fluid flow between the reservoir and the second end of the cylinder when positioned between the port opening and the second end to pressurize the second end;
a lever pivotably connected to the housing to pivot about an axis transverse the cylinder axis between a rest position and a fully actuated position;
a push rod having a first end and a second end, the push rod having a threaded portion near the first end with a threaded connection between the threaded portion and the lever and the second end operatively associated with the piston so that as the lever is pivoted between the rest position and the fully actuated position the piston is moved between the starting position and the pressurized position;
an externally threaded insert threadably received in the housing along the cylinder axis, the externally threaded insert being operatively associated with the push rod to move the second end of the push rod along the cylinder axis toward the second end of the cylinder as the externally threaded insert is rotated in a first direction within the housing and to move the second end of the push rod away from the second end of the cylinder as the externally threaded insert is rotated in a second direction within the housing, whereby the select starting position of the piston may be selected by a user;
and
the threaded connection between the threaded portion of the push rod and the lever being configured to maintain the lever in a select rest position relative to the housing as the externally threaded insert and thereby the push rod are rotated in either of the first and second directions to vary the select start position of the piston.

6 more elements

Dependencies are inferred from the claim text.

Master cylinder lever for a hydraulic disk brake having on the fly dead-band adjustment

Life of this patent

Master cylinder lever for a hydraulic disk brake having on the fly dead-band adjustment

Life of this patent

Abstract

Claims17