Gear wheel mechanism

A hydrostatic gear wheel mechanism, comprising:

• a housing having pressure and suction ports;
• first and second intermeshing gear wheels mounted in said housing, said gear wheels having front faces and pluralities of radially extending teeth, said teeth defining intermediate spaces and bases between adjacent pairs of said teeth, one of said gear wheels being an outer hollow gear wheel with radially inwardly projecting teeth, the other of said gear wheels being a pinion with radially outwardly projecting teeth mounted within said hollow gear wheel;
• a work space defined between a radially inner periphery of said outer hollow gear wheel, a radially outer periphery of said pinion and the teeth mating between sadi outer hollow gear wheel and said pinion, opposite ends of said work space being connected to said pressure and suction ports;
• an intermediate member in said work space between said gear wheels;
• recesses on sadi front faces of said gear wheels, said recesses extending radially relative to said wheels from said bases between said teeth of said gear wheels and being connected with said work space at said bases;
• means for connecting each of said recesses only at one end thereof with said work space while the other end thereof ends within the respective gear wheel, for alternating direct fluid communication of each of said recesses with said pressure and suction ports, and for preventing direct fluid communication between said pressure and suction ports through said recesses and said work space as said gear wheels rotate such that said recesses convey fluid for lubrication only.