Patent ID: 9732749
Date: 2017-08-15
CPC Classifications: F04C

Claim:
1. A rotary lobe pump for conveying a fluid medium containing solids, comprising: wherein the rotational axes of the two rotary lobes lie in a first plane and are spaced a first minimum length apart from each other in the first plane, wherein the outer peripheries of the two rotary lobes partially intersect each other, and wherein the inlet opening extends through the wall between the outer surface to the inner surface and has a converging cross-section shape that decreases in the feeding direction from the outer surface to the inner surface, the inlet opening having a first flow length that spans from the outer surface to the inner surface in the feeding direction, the inlet opening further including a second length defined at the outer surface between opposing surface portions of the outer surface and a third length defined at the inner surface between opposing surface portions of the inner surface, the second length and the third length each having a respective parallel, spaced relationship with the first plane and are respectively disposed transverse to the feeding direction, wherein the inlet opening guides the fluid medium in between the two rotary lobes in the feeding direction, wherein the outlet opening extends through the wall between the inner surface and the outer surface and has a converging cross-section shape that decreases in the feeding direction from the inner surface to the outer surface, the outlet opening having a second flow length that spans from the inner surface to the outer surface in the feeding direction, the outlet opening further including a fourth length defined at the inner surface between opposing surface portions of the inner surface and a fifth length defined at the outer surface between opposing surface portions of the outer surface, the fourth length and the fifth length each having a respective parallel, spaced relationship with the first plane and are respectively disposed transverse to the feeding direction, wherein the converging cross-section of the inlet opening through the wall that decreases in the feeding direction is a continuous decreasing convergence that occurs along the entire first flow length of the inlet opening, and continuously decreasingly converges in a direction from the outer surface to the inner surface, wherein the converging cross-section of the outlet opening through the wall that decreases in the feeding direction is a continuous decreasing convergence that occurs along the entire second flow length of the outlet opening, and continuously decreasingly converges in a direction from the inner surface to the outer surface, wherein the third length of the inlet opening at the inner surface is less than each of the first minimum length between the axes of the two rotary lobes and the fourth length at the inner surface of the outlet opening, respectively, and wherein the fourth length at the inner surface of the outlet opening is greater than the first minimum length between the axes of the two rotary lobes.