Patent ID: 9651634
Date: 2017-05-16
CPC Classifications: B60T,G01R

Claim:
1. A brake master cylinder comprising a BLS module for controlling the switching on of a brake lamp according to an operation of a piston provided to reciprocate within a cylinder body, wherein the BLS module comprises: a hollow portion formed in the cylinder body at a middle portion of the cylinder body in a lengthwise direction of the cylinder; a guide hole formed in the cylinder body at a lower portion of the cylinder body below the hollow portion in the lengthwise direction of the cylinder body; a magnet disposed inside the guide hole so that the magnet slides in the lengthwise direction of the cylinder body inside the guide hole; an actuating member connected to an end of the piston so as to be moved together with the piston as the piston is moved in the hollow portion of the cylinder; a Hall sensor installed in the cylinder body at a location corresponding to the magnet for detecting a magnetic flux density of the magnet; and a shielding member disposed inside the guide hole and sliding by the actuating member for shielding the Hall sensor from the magnet.