Selectively controlled dual delivery pump, particularly for motor vehicle application

A selectively controlled dual delivery pump, particularly for motor vehicle application, comprising a stator casing, an impeller housing within said stator casing, a bidirectional rotating pump impeller within said impeller housing, a manifold room within said stator casing, shutter means in said manifold room, said shutter means defining and hermetically sealing from each other a first and a second manifold chambers in said manifold room, two separate communication conduits extending tangentially from said impeller housing and opening at either said manifold chambers so as to divert a fluid flowing in said impeller housing tangentially to said pump impeller with respect to both rotation directions of said pump impeller, a delivery outlet in each said manifold chamber, a separate delivery manifold departing from each said delivery outlet, a valve seat at said delivery outlet in each manifold chamber in front of said shutter means, said shutter means comprising an elastic membrane for selectively shutting off said valve seats, thereby the rotation direction of said pump impeller causes a high pressure condition in one manifold chamber and a low pressure condition in the other manifold chamber so that the elastic membrane is pushed against and cuts off the valve seat in the manifold chamber at the low pressue condition and shuts off flow in the delivery manifold departing therefrom.