A scroll casing has a scroll portion, a discharge portion provided with a discharge port, and a tongue portion. An extended plate has, in a cross section obtained by cutting in a thickness direction, a change point, at which an enlargement ratio of an area of the cross section is enlarged so as to be larger on a downstream side than that on an upstream side due to a change of inclination. In the extended plate, an angle θ1, and an angle θ2 satisfy a relationship of either 0≤θ2<θ1 or 0<θ2≤θ1. A distance L1 and a distance L2 satisfy a relationship of L2<L1.

A self-priming assembly for a multi-stage pump is provided. The self-priming assembly can have a first diffuser, a second diffuser, and an impeller. The first and second diffusers each include a central portion, a diffuser axis, an arcuate channel within the central portion, and a passage extending through the central portion. The first diffuser and the second diffuser are configured to be combined and receive the impeller therebetween with the first diffuser axis, the second diffuser axis, and the impeller axis aligned.

A neck-hanging fan, comprises a housing that can be worn on the neck and a fan assembly, wherein the two extended tail ends of the housing are provided with an accommodating chamber, and an air duct communicating with the accommodating chamber is formed in the housing, a fan assembly is arranged in the accommodating chamber, an air inlet hole communicating with the accommodating chamber is arranged on the housing, and a plurality of air outlet holes communicating with the air duct are arranged on the outer wall of the housing, and the plurality of air outlet holes are distributed along the extension direction of the air duct. The end of the air outlet away from the fan assembly is provided with a wind gathering plate extending into the air duct, wherein a plurality of wind gathering plates are provided.

A fan including: a motor stator; an axial diffuser, fixedly connected to the motor stator and comprising an outer cylinder, a main body portion disposed in the outer cylinder, and diffuser blades connected to the outer cylinder and the main body portion, the diffuser blades separating an annular space between the outer cylinder and the main body portion into more than one pressure diffusion ducts, the main body portion being provided with a central shaft hole; an air inlet cover, fixedly connected to the axial diffuser, the air inlet cover and the axial diffuser forming an impeller chamber and an annular no-gate channel around the impeller chamber, the annular no-gate channel communicating with the impeller chamber and the pressure diffusion ducts, and the air inlet cover being provided with an air inlet; and an impeller, disposed in the impeller chamber and used to introduce air from the air inlet.

A fan including: a motor stator; an axial diffuser, fixedly connected to the motor stator and comprising an outer cylinder, a main body portion disposed in the outer cylinder, and diffuser blades connected to the outer cylinder and the main body portion, the diffuser blades separating an annular space between the outer cylinder and the main body portion into more than one pressure diffusion ducts, the main body portion being provided with a central shaft hole; an air inlet cover, fixedly connected to the axial diffuser, the air inlet cover and the axial diffuser forming an impeller chamber and an annular no-gate channel around the impeller chamber, the annular no-gate channel communicating with the impeller chamber and the pressure diffusion ducts, and the air inlet cover being provided with an air inlet; and an impeller, disposed in the impeller chamber and used to introduce air from the air inlet.

Disclosed are pumps designed to make priming more efficient and therefore reduce priming time. The disclosed pumps include one or more deflection structures that prevent fluid moving through a diffuser of the pump from continuing in a circular path and instead divert the fluid in a different direction that leads directly to an outlet of the pump. This deflection reduces air bubble accumulation inside the pump while priming and makes it easier for air to escape through the pump outlet. Making it easier for air to escape the pump outlet ultimately allows air to escape the pump faster during priming, reducing back pressure caused by trapped air pockets inside the pump and improving priming performance.

A blower includes a first extension having a first discharge port formed in a first wall, a second extension having a second discharge port formed in a second wall facing and spaced apart from the first wall, a fan provided below the first and second extensions to guide air toward each of the first tower and the second tower, a first gate provided inside the first tower or protruding from the first wall, a second gate provided inside the second tower or protruding from the second wall, a first guide motor to change a position of the first gate, and a second guide motor to change a position of the second gate.

A blower device includes a pair of fans, a housing, and a lid. The pair of fans generates an airflow on one side in the axial direction along the central axis and is coaxially arranged. The housing has a tubular shape extending along the central axis, accommodates the pair of fans, and has two end surfaces opened in the axial direction. The lids cover axial end surfaces of the housing and provide ventilation. The lid includes an annular portion in contact with the inner peripheral surface of the housing and including a through hole penetrating in the radial direction. The housing includes an engagement protrusion that protrudes radially inward from the inner peripheral surface and engages with the periphery of the through hole.

A throttle valve for a centrifugal compressor includes a body having a central passage and one or more diverter flow paths. The central passage is formed by an inner surface of the body, each diverter flow path has an inlet and an outlet, and the one or more diverter flow paths are configured to induce a swirl within a fluid flow through the central passage while a portion of the fluid flow passes through the one or more diverter flow paths. The throttle valve also includes at least one blade disposed within the central passage. The at least one blade is configured to direct the portion of the fluid flow to the inlets of the one or more diverter flow paths while the at least one blade is in a partially open position.

A throttle valve for a centrifugal compressor includes a body having a central passage and one or more diverter flow paths. The central passage is formed by an inner surface of the body, each diverter flow path has an inlet and an outlet, and the one or more diverter flow paths are configured to induce a swirl within a fluid flow through the central passage while a portion of the fluid flow passes through the one or more diverter flow paths. The throttle valve also includes at least one blade disposed within the central passage. The at least one blade is configured to direct the portion of the fluid flow to the inlets of the one or more diverter flow paths while the at least one blade is in a partially open position.