Brake fluid level monitoring apparatus

Claim 1

Apparatus for monitoring the increasing level of fluid within a master cylinder reservoir of a hydraulic brake system of an automobile during air bleeding operations while fluid is pumped into the reservoir from brake fluid lines, the apparatus comprising: a base support member for engaging a master cylinder about an opening to the fluid reservoir of the master cylinder during air bleeding operations while fluid is pumped into the reservoir from brake fluid lines; a housing forming an internal fluid collection cavity, the housing being supported by the base support member to position said cavity at least partially within the interior of said fluid reservoir, said cavity opening to the interior of the reservoir to permit fluid pumped into the reservoir from brake fluid lines to flow within said cavity during said air bleeding operations such that the increasing level of fluid within said cavity corresponds with the increasing level of fluid within said reservoir; an electrically non-conductive float positioned with said fluid collection cavity for sensing the fluid level within said fluid collection cavity with the elevation of the float within said cavity increasing simultaneously as the fluid level increases; a permeable member positioned over said cavity opening to entrap said float within said cavity and to permit fluid to enter within said cavity; an actuator control arm engaged to and projecting axially from said float, the arm extending to the exterior of said fluid collection cavity housing to within an internal guide chamber of an elongated guide member projecting above said base support member, said guide chamber being in coaxial alignment with said cavity and laterally guiding said control arm permitting said arm to travel longitudinally within said guide chamber responsive to the elevation level of the float within said collection cavity; an electrical control station responsive to the actuator control arm for indicating the elevated position of the control arm within said elongated guide chamber, the control station including a magnet member engaged about one terminal end of said control arm and within said elongated guide chamber, a magnetically operable switch means positioned laterally adjacent to said guide member about the exterior of said guide member and elevated relative to said collection cavity, said switch means including overlapping contacts for electrically making and breaking an electrical circuit responsive to the elevated position of said magnetic member within said chamber relative to the elevation of said overlapping contacts, said magnet member having a magnetic field strength sufficient to actuate said contacts when said magnet is elevated to a position within said guide chamber laterally adjacent to said contacts; and an indicating device electrically coupled to said switch means and adapted to indicate the making and breaking of said electrical circuit.