Patent ID: 10837462

Abstract:
A volute pump for delivering a liquid containing fibrous substances. The volute pump includes an impeller (1) rotatable together with a rotational shaft (11), and an impeller casing (5) having a suction port (3) and a volute chamber (7). A groove (18), extending from the suction port (3) to the volute chamber (7), is formed in an inner surface of the impeller casing (5). The impeller (1) includes a hub (13) to which the rotational shaft (11) is fixed, and a sweep-back vane (2) extending helically from the hub (13). The sweep-back vane (2) includes a leading edge portion (2a) extending helically from the hub (13), and a trailing edge portion (2b) extending helically from the leading edge portion (2a). The leading edge portion (2a) has a front-side curved surface (2e) extending from an inner end (2c) to an outer end (2d) of the leading edge portion (2a).