A propeller fan includes a hub rotatable about an axis, and a plurality of blades extending radially outward from an outer peripheral surface of the hub. A ring surrounds the plurality of blades and is connected to each blade tip. A maximum camber location is on a camber line where a distance from a chord line to the camber line in an arc-shaped cross section of each blade about the axis is maximum. An axial height is from a trailing edge to the camber line in a direction along the axis. Each blade has a first portion provided inside in the radial direction of rotation and whose axial height at the maximum camber location is substantially constant, and a second portion provided outside in the radial direction of rotation and whose axial height at the maximum camber location increases toward the blade tip.

One feature pertains to an acoustic attenuation device. The acoustic attenuation device comprises a fan assembly, the fan assembly including at least one fan module that directs airflow in at least one direction, wherein the at least one fan module includes a top surface and a bottom surface, a plurality of air deflectors mounted to the top surface and the bottom surface of the at least one fan module, wherein the plurality of air deflectors include a plurality of surfaces, and wherein at least one of the plurality of surfaces is an angled surface that redirects the airflow 90-degrees, and acoustic attenuating foam, wherein the acoustic attenuating foam has a two-dimensional (2-D) surface and is applied to interior surfaces of the plurality of surfaces.

This refrigerant vessel component (2, 4, 7) for a refrigeration circuit (100), comprises a shell (10) extending along a longitudinal axis (X) delimiting an internal volume (V), in which circulates a refrigerant fluid (R), whereas the refrigerant vessel component (2) comprises an inner shell (20) located radially inside the shell (10) and extending on at least a portion of the circumference of the shell (10), and whereas the inner shell (20) is at least partly formed of perforated material.

A method of forming a balanced rotor blade assembly includes measuring a weight of a plurality of sub-components of the rotor blade assembly excluding a core. A configuration of a core of the rotor blade assembly is determined. In combination, the core and the plurality of sub-components achieve a target weight distribution and moment. The core is then fabricated and assembled with the plurality of sub-components to form a rotor blade sub-assembly.

A modular fan cover assembly for inclusion on an electric motor is selectively configurable for degrees of reduced noise operation. The modular fan cover assembly includes a plurality of cooperating components arranged to direct fluid communication through the assembly. The components may include, for example, a fan cover defining a fan chamber for enclosing the fan, an inlet cover including an inlet chamber and a plurality of inlet apertures, and a silencing insert selectively includable with the fan cover assembly that may include one or more silencing features. The selective combination of the components can redirect airflow through various turns or bend in the modular fan cover assembly to trap or suppress noise propagating from the electric motor. The modular fan cover assembly may be operatively equipped with a blower assembly.

A blower unit can include an outer housing, an inlet subassembly, a fan subassembly, an outlet subassembly, and a grommet. The outer housing can have an aperture extend along a first axis between first and second ends. The inlet subassembly can be received in the first end of the aperture. The fan subassembly can be received in the aperture adjacent to the inlet subassembly and include at least one wire. The outlet subassembly can be received in the second end. The grommet can be positioned between at least part of the second end and the outlet subassembly. The at least one wire can extend through the grommet. The grommet can seal against the at least one wire. The grommet can seal between the outer housing and the outlet subassembly.

A fan frame body structure includes a first frame body. The first frame body has a first upper end, a first lower end, a first frame wall and a first main flow way. The first main flow way passes through the first frame body and is formed with a first main inlet and a first main outlet respectively at the first upper end and the first lower end. A first subsidiary flow way is disposed in the first frame wall. The first subsidiary flow way is in parallel the first main flow way. The first subsidiary outlet is positioned at the first upper end of the first frame body in flush with and in adjacency to the first main 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.

A vibration body unit includes: a vibration body; an inner cylinder that surrounds a circumference of the vibration body and that is elastically deformable; an outer cylinder that surrounds a circumference of the inner cylinder and that has an attachment section which is attached to a base part; a plurality of first spacers that are interposed between the vibration body and the inner cylinder and that are arranged to be spaced in a circumferential direction; and a plurality of second spacers that are interposed between the inner cylinder and the outer cylinder and that are arranged to be spaced in a circumferential direction, wherein the plurality of first spacers and the plurality of second spacers are arranged such that at least part of each of the plurality of first spacers faces each of the plurality of second spacers in a radial direction across the inner cylinder.

A first elastic member is interposed between an outer peripheral surface of the circular core back portion and an inner wall surface of the second motor housing in a radial direction, both outer peripheral ends of the core back portion in the axial direction of the rotor are covered with the first elastic member, the first elastic member is assembled by being pinched between end surfaces of the first motor housing and the second motor housing which faces each other, and a second elastic member is assembled by being stacked between the bearing assembled in one of the pair of bearing housings and the bearing housing.