Supply Air device (1) for controlling supply air flow to a building space, comprising a chamber (2) having a supply air inlet (3) and an air outlet (4). A first tube (10) in the chamber is connected at an open first end (11) to the supply air inlet, wherein the first tube has a side wall (13) which is permeable to air. A throttle member (30) is slidably connected to the first tube to change a degree of exposure of the side wall to control air flow through said side wall to the outlet. The exposable side wall comprises a layer of porous material (14) through which air is discharged.

A humidifier includes a base housing having a receiving cavity and an air outlet, a water tank having a vapor outlet, a vaporizing arrangement having a vaporizer and a fan, and a waterproof arrangement. The waterproof arrangement includes a blocking member movably mounted on the base housing to selectively move between an opened position and a closed position, wherein when the water tank is detached from the base housing, the blocking member is driven to block the air outlet so as to prevent water from passing through the air outlet, wherein when the water tank is attached on the base housing, the blocking member is driven to unblock the air outlet so as to allow air created by the fan to flow through the air outlet.

A humidifier includes a base housing having a receiving cavity and an air outlet, a water tank having a vapor outlet, a vaporizing arrangement having a vaporizer and a fan, and a waterproof arrangement. The waterproof arrangement includes a blocking member movably mounted on the base housing to selectively move between an opened position and a closed position, wherein when the water tank is detached from the base housing, the blocking member is driven to block the air outlet so as to prevent water from passing through the air outlet, wherein when the water tank is attached on the base housing, the blocking member is driven to unblock the air outlet so as to allow air created by the fan to flow through the air outlet.

Fabric drop-down diffusers are disclosed. An example drop-down diffuser includes a hoop to be supported adjacent an end of an air duct, and a first fabric sheet to hang downward from the hoop. The first fabric sheet to define a first wall of an air chamber adjacent the hoop on a side of the hoop opposite the air duct. The first fabric sheet to completely surround the air chamber along a circumferential path corresponding to the hoop. The hoop to be transverse to the air duct and positioned so that air delivered by the air duct is to pass through the hoop and into the air chamber. The drop-down diffuser also includes a second fabric sheet to be coupled to the first fabric sheet. The second fabric sheet to define a second wall of the air chamber.

The invention relates to an air exhaust valve (1). The air exhaust valve (1) comprises an inner baffle element (10) located at a radially inside position and an outer baffle element (20) located at a radially outside position and surrounding said inner baffle element (10) for defining an air flow space (70) between said inner baffle element (10) and said outer baffle element (20). There are provided an inner plurality of slits or grooves in said inner baffle element (10) and/or an outer plurality of slits or grooves (21) in said outer baffle element (20).

A screen cover for attaching to an open end of a conduit of a water heater is provided. The screen cover includes a first diametric portion having a first diameter and a second diametric portion having a second diameter. The first diameter is greater than the second diameter. The first and second diametric portions are coaxially aligned and configured to allow flow of air or gas therethrough. The screen cover includes a shoulder portion defined between the first diametric portion and the second diametric portion. The screen cover further includes a mesh disposed at a first opening of the first diametric portion. The mesh prevents entry of external objects into the water heater through the open end of the conduit.

This application discloses a wind pressure-driven air intake device for natural ventilation of zero power consumption. Such a device comprises multiple tunnels being arranged around a common central chamber, each having an inflow valve at its inner end connecting the central chamber and an outer end open to ambient airflow. The inflow valve allows only inward flow from a corresponding tunnel into the central chamber. The central chamber has an opening allowing airflow exit to a space to be ventilated. The device is capable of capturing ambient wind flow and wind pressure to be fed to the vented space regardless of wind flow direction towards the device, with no need for a powered air driver.

An air supply device with an annular air outlet and a design method thereof are provided. The device includes an air delivery section arranged in a horizontal plane and communicated with a plurality of air-out sections, wherein an axis of each of the plurality of air-out sections is in a vertical direction; the air delivery section and the plurality of air-out sections are respectively provided with air return ducts communicated with each other, the air return ducts each have a fresh air duct provided therein; an axis of the fresh air duct is parallel to an axis of corresponding air return duct of the air return ducts, and the fresh air duct and the corresponding air return duct are equal in length, the plurality of air-out sections are arranged above office cubicles in a room.

An air supply device with an annular air outlet and a design method thereof are provided. The device includes an air delivery section arranged in a horizontal plane and communicated with a plurality of air-out sections, wherein an axis of each of the plurality of air-out sections is in a vertical direction; the air delivery section and the plurality of air-out sections are respectively provided with air return ducts communicated with each other, the air return ducts each have a fresh air duct provided therein; an axis of the fresh air duct is parallel to an axis of corresponding air return duct of the air return ducts, and the fresh air duct and the corresponding air return duct are equal in length, the plurality of air-out sections are arranged above office cubicles in a room.

An air discharge device is configured to discharge an air flow. The air discharge device includes a main hole for discharging an air flow as a working air flow, an auxiliary hole provided around the main hole to discharge a support air flow, and a vortex suppression structure configured to suppress development of vortices generated in a velocity boundary layer of the working air flow at a downstream side of an outlet of the main hole. This vortex suppression structure is configured to make a central portion of the thickness of the velocity boundary layer of the working air flow at the downstream side of the outlet of the main hole to be closer to a mainstream of the support air flow, at the downstream side of the outlet of the main hole.