Ebara Corporation

Hiromi Sakacho

Masakazu Yamamoto

Koji Isemoto

Masashi Obuchi

Hiroshi Uchida

Yoshio Miyake

Masahito Kawai

Miho Isono

Makoto Kobayashi

Tsuyoshi Maeda

Kikuichi Mori

Seigo Katsuta

Kunihiko Fujii

Masayoshi Moriya

Seiichirou Yamada

Kenta Tokairin

Yoichi Nakamura

Yoshiaki Miyazaki

Junya Kawabata

The present invention relates to a volute pump for delivering a liquid containing fibrous substances. The volute pump includes an impeller () having a vane (), and an impeller casing () which houses the impeller () therein. The impeller casing () includes a volute chamber (), a suction port () and a discharge port () which communicate with the volute chamber (), and a tongue portion () which forms a starting portion of the volute chamber (). A groove (), extending from the suction port () to the volute chamber (), is formed in an inner surface of the impeller casing (). An intersection point (B), where a terminal end of the vane () passes across the groove () as viewed from an axial direction of the impeller (), is located at an opposite side from the tongue portion () with respect to a central point of the impeller ().

Volute pump

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

The present invention relates to a volute pump and particularly provides a volute pump for delivering a liquid containing fibrous substances and solid substances, while preventing these substances from obstructing the pump. The volute pump includes a pump casing () having a protrusion () projecting into a flow passage () and separating a starting end of a volute from a terminal end of a volute. The protrusion () faces a liquid outlet () of an impeller (). A radius of curvature (Rb) of a cross section of a distal edge of the protrusion () at its one side end () is larger than a radius of curvature (Ra) of the cross section of the distal edge of the protrusion () at other side end (). The other side end () faces a main plate (), while the one side end () is located opposite to the main plate ().

A casing liner used for a sewage pump includes a surface to face an edge of a blade of an impeller when the casing liner is assembled with the impeller into the sewage pump. At least one groove with given width is formed in at least a part of the surface. The groove includes a first section with given depth, which is located on the side close to a rotational center of the impeller, a second section smaller in depth than the first section, which is located on the side far from the rotational center of the impeller, and a third section that is an inclined face connecting the first and second sections, the first to third sections being arranged in a width direction of the groove.

Casing liner for sewage pump and sewage pump with the same

A non-clogging type pump impeller includes: a fluid passage provided in an approximately cylindrical body and connecting a suction port to a discharge port. The fluid passage has a vortex shape as viewed from an axial direction. A first recess, which is sunk downwardly in the axial direction, is formed on a first end surface of the approximately cylindrical body so as to surround a boss. A second recess, which is sunk upwardly in the axial direction, is formed on a second end surface of the approximately cylindrical body so as to surround the suction port. At least one communication hole provides fluid communication between the first recess and the second recess. Sewage in the second recess is introduced into the first recess through the at least one communication hole to thereby effectively remove an air pocket trapped on the first end surface of the impeller and in the first recess.

Pump impeller and submersible pump having such pump impeller

A full-circumferential flow pump has a circumferential fluid passage between a sheet metal pump casing and a motor provided in the pump casing. The full-circumferential flow pump comprises a suction-side casing having a suction nozzle, and an outer cylinder connected to the suction-side casing and accommodating the canned motor therein. The suction-side casing and the outer cylinder have flanges, respectively extending radially outwardly from an open ends thereof. The adjacent flanges of the suction-side casing and the outer cylinder are clamped by clamping flanges to connect the suction-side casing and the outer cylinder.

Nozzle structure for a full-circumferential flow pump

A pump casing made of sheet metal has an outer casing having a suction nozzle, and an inner casing housed in said outer casing and spaced therefrom. A resilient seal is disposed in a gap defined between the outer casing and an inner casing. An impeller is rotatably disposed in the inner casing with a clearance defined between a liner portion of the inner casing and the impeller. The resilient seal is effective to absorb deformations of the outer casing, such deformations of the outer casing are not transmitted to the inner casing.

Pump casing made of sheet metal

A full-circumferential flow pump has a circumferential fluid passage between a pump casing and a motor provided in the pump casing. The full-circumferential flow pump comprises a suction-side casing having a suction nozzle, and an outer cylinder connected to the suction-side casing and accommodating the canned motor therein. The suction-side casing and the outer cylinder have flanges, respectively extending radially outwardly from an open ends thereof. The adjacent flanges of the suction-side casing and the outer cylinder are clamped by clamping flanges to connect the suction-side casing and the outer cylinder.

Full-circumferential flow pump

A pump mounting structure of a canned submersible motor for a deep well pump is disclosed. The motor comprises a stator chamber and bearing brackets provided on opposite sides of the stator chamber. The bearing bracket on a load side of the motor includes a pump mounting flange for supporting the pump thereon. The improvement consists of a pump suction port being formed in the load side bearing bracket to thereby make the load side bearing bracket serve as a pump suction casing, and of the pump mounting flange being constituted as a pump body mounting flange. By this means, heat generated in the stator chamber is dissipated efficiently by the water passing through the suction port provided in the bearing bracket. Also, as a pump suction casing is not necessary, an axial length of the pump can be shortened and the number of parts can be reduced.

Pump mounting structure of canned submersible motor for deep well pump

A canned motor equipped with a stator chamber, a load side bearing bracket and an opposite side bearing bracket on the load side and opposite side of the stator chamber. The stator chamber is formed by integrally welding a stator core, an outside can, an inside can, a load side end plate and opposite side end plate. The load side bearing bracket and the opposite side bearing bracket each includes a bearing boss supporting a radial bearing and a shaft seal thereon. The improvement consists of the end plate and the bearing bracket on the load side being integrally formed to provide a single shell structure and the inside can being welded to the bearing boss of the load side bearing bracket. By this arrangement, the number of components required for the motor is reduced, axial length of the motor is shortened and heat radiation from the end surface of the stator chamber on the load side is enhanced.

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Tokyo, Japan

Hiromi Sakacho