Patent attributes
A pump aggregate (A) comprises a housing (1, 2, 4), a high-pressure pump (5) and a low-pressure pump (6) disposed in the housing, an oil-immersed electric motor (7), a return connection point (8) connected to a return line (9), and a valve arrangement (V) mounted between separated discharge outlet ports of both pumps (5, 6) and a pressure connection point (P). The valve arrangement (V) comprises at least a low-pressure change-over valve (U), a check valve (R) for combining discharge flows of both pumps (5, 6), and a system pressure-limiting valve (DB). At least the low-pressure change-over valve (U) and the check valve (R) are arranged in an interior of the housing (1, 2, 4) and are connected so that the discharge flows of both pumps (5, 6) are combined in the housing interior for a single pressure outlet (13, P′) of the housing, and wherein the system pressure-limiting valve (DB) is connected to the pressure outlet and is mounted on an exterior of the housing.
