GB700487A - Liquid ring pump - Google Patents

Abstract

700,487. Liquid-ring pumps. NASH ENGINEERING CO. Dec. 5, 1951 [Feb. 15, 1951), No. 28509/51. Class 110 (1) A liquid-ring gas pump comprises a rotor which runs in a lobed pumping chamber having a conical inner boundary, and a lobe of progressively increasing depth from the end at which the diameter of the conical inner boundary is greatest towards the end at which it is least. In the pump shown in Figs. 11, 17 and 18, comprising a rotor 3c coacting with ported cones 4c and lobes 10c, the lobes are of conical form, whereby the variation, along the axis of the pump, of the rotor displacement volume is matched by a corresponding variation of the displacement volume of each lobe. This minimizes the formation of parasitic currents, loss of liquid through the inlet and outlet ports and other adverse effects which would occur if the lobes were of conventional form. The radius of each lobe increases from Rc to Rc2, as shown, the corresponding offset of the axis of the lobe with respect to the axis of rotation increasing from Oc to Oc2. Instead of increasing, the offset may decrease or be constant. Alternatively, the radius may be constant while the offset increases. In the embodiment shown in Fig. 19, each lobe 34 is lopsided, being formed by an arc 37 of radius Rd1 merging with an arc 39 of radius Rd2. The axis of the lobe is of increasing offset with respect to the axis 33 of rotation, so that the centres shift progressively from 41 and 42 at one end of the lobe to 38 and 40 respectively at the other end. All these constructions incidentally give a tapered form to the lands 7c, Figs. 17 and 18, whereby each rotor blade crosses the boundaries between the lobes and lands progressively instead of abruptly, thereby reducing noise, vibration and cavitation. Specifications 379,891 and 462,208 are referred to.