Center driven pressure clamped hydraulic pump

A pressure clamped hydraulic gear pump for pumping a fluid, the pump comprising:

• a pump housing defining a central axis and including a front cover, a pumping means housing and a rear cover positioned in axially disposed relation to one another, and clamped together with hydraulic fluid pressure, with the rear cover including an inlet and an outlet, the housing being adapted for installation into a cavity;
• pumping means located in the pumping means housing for drawing fluid into the inlet at a first pressure and pumping the fluid from the outlet at a second pressure greater than the first pressure;
• means for applying the second pressure to at least the rear cover to hold the front cover, pumping means housing and rear cover together in the axially disposed relation, by hydraulic fluid pressure, without applying a separate clamping force to the components in a direction parallel to the housing axis;
• and
• a drive shaft extending from the housing along the central axis and operatively connected to the pumping means for drawing fluid into the inlet at a first pressure and pumping the fluid from the outlet at a second pressure greater than the first pressure, when the drive shaft is rotated about the axis.