Fluid control cylinder assembly for automobile brake system

A brake fluid control cylinder assembly for use in a brake system of an automobile having a clutch pedal and a brake pedal comprising:

• a cylindrical housing having a first end and a second end;
• first and second coaxially-spaced cylinder chambers in said housing;
• an internal flange wall between said cylinder chambers;
• an axial hole through said flange wall communicating between said cylinder chambers;
• respective first and second cup-shaped pistons axially movable in said first and second cylinder chambers, said pistons each having a hollow central portion and a bottom;
• respective first and second piston rods in said cylinder chambers each having one end thereof axially slidably mounted in said hollow central portion of respective first and second pistons, said second piston rod extending through said axial hole in said flange wall;
• a first brake fluid inlet in said first end of said housing communicating with said first cylinder chamber and having a first valve seat therein;
• first valve means on the other end of said first piston rod engageable with said first valve seat;
• a first piston spring means in said first cylinder chamber for resiliently urging said first piston away from said first end of said housing;
• a first piston rod spring means in said hollow central portion of said first piston for resiliently urging said first piston rod toward said first end of said housing and said first valve means toward sealing engagement with said first valve seat;
• a first brake fluid outlet for said first cylinder chamber through said housing disposed between said first valve seat and said first piston;
• a first outlet check valve means in said first outlet for providing outlet flow from said first cylinder chamber at a predetermined fluid pressure;
• a second valve seat in said flange wall at said axial hole;
• a second valve means sealingly and slidably mounted on said second piston rod in said second cylinder chamber engageable in sealing relationship with said second valve seat;
• a second piston spring means in said second cylinder chamber having one end connected to said second piston and the other end connected to said second valve means for resiliently urging said second valve means toward engagement with said second valve seat;
• a second piston rod spring means in said hollow central portion of said second piston for resiliently urging said second piston rod into engagement at the other end thereof with said first piston;
• a second brake fluid inlet through said housing communicating with said axial hole in said flange wall between said second valve seat and said first cylinder chamber;
• seal means between said flange and said second piston rod and between said second brake fluid inlet and said first cylinder chamber for sealing said axial hole in said flange wall between said second fluid inlet and said first cylinder chamber;
• a second brake fluid outlet through said housing for said second cylinder chamber disposed between said second piston and said second valve seat;
• second outlet check valve means in said second outlet for providing outlet flow from said second cylinder chamber at a predetermined fluid pressure;
• and
• clutch pedal operated means operated by depressing the clutch pedal for moving said piston rods to urge said first and second valve means into engagement with the respective valve seats, and for limiting return movement of said second piston upon release of the clutch pedal.