Antilocking mechanism for vehicle brake system

Claim 1

In an antilocking mechanism for use with the brake system of a wheeled vehicle having a master cylinder and a plurality of wheels, wherein each wheel has a wheel cylinder for operating a brake, the mechanism being of the type wherein brake fluid is returned from said wheel cylinders to said master cylinder by pump pistons in the event of locking, and of the type wherein a plurality of said pump pistons are operated by a common motor-driven eccentric drive mechanism, the improvement comprising integrated fluid path and fluid pumping means including: a common housing for said fluid path and fluid pumping means, said housing being cylindrically symmetrical and thereby defining an axis of cylindrical symmetry; chamber means including a central cavity formed in the interior of said housing, said chamber means being located at one axial end of said housing and said cavity being located centrally within said chamber means and straddling said axis; a plurality of pistons slidably mounted in the interior of said housing for reciprocating movement radially of said housing and extending outwardly from said central cavity and angularly separated by 360 degrees divided by the number of said pistons; said pistons each having a portion extending into said cavity; a common eccentric mounted in said cavity for rotation about said axis and engaging said piston portions for thereby sequentially operating each of said pistons; the interior of said housing being formed with a plurality of bores forming first and second conduit means for each of said pistons, said conduit means defining a pair of parallel fluid paths between the master cylinder and at least one of said wheel cylinders, and said mechanism further including a solenoid-actuated valve enclosed within one of said bores and controlling fluid flow in one of said parallel paths of each said pair, and a unidirectional valve enclosed within another of said bores and controlling fluid flow in the other of said parallel paths of each said pair, said bores being axially displaced from said chamber means toward the other axial end of said housing but extending axially into fluid communication with said chamber means.