The present disclosure concerns the field of vacuum cleaners and, in particular, those which have a filter bag for collecting air entrained detritus. The invention relates especially to a vacuum cleaner which reduces the exposure to the operator of dust and contaminated matter collected during cleaning when replacing the filter bag. The invention provides a vacuum cleaner comprising a suction drive unit in fluid communication with a vacuum chamber for accommodating a filter cartridge, the vacuum chamber itself being fed by a fluid inlet port in communication with a nozzle via which air is drawn into the vacuum chamber when the suction drive unit is in operation, wherein the filter cartridge comprises a gas-porous membrane including wall portions which define a filter interior, the cartridge having an airflow inlet at one end through which air-entrained dirt enters the filter, with dirt retained in the interior and air passing through the gas-porous membrane, wherein the chamber is configurable between open and closed configurations, so that in the closed configuration the cartridge filter is enclosed and constrained within the vacuum chamber with the cartridge inlet disposed so as to be fed by the fluid inlet port, and in the open configuration the constraint is at least partially removed so that the cartridge is free to be removed from the chamber by travel in a removal direction.

The present invention relates to a filter medium, a filter arrangement for the filtration of gas-particle systems comprising such a filter medium, a method for depleting pathogens and/or allergens from the air and other gases by means of such a filter medium, and the use of the filter medium for depleting pathogens and/or allergens from the air and other gases. The filter medium includes at least one acid-functionalized layer comprising at least one carrier material and at least one fruit acid having a pks1 value of 0 to 7. The at least one acid-functionalized layer is free of added C.sub.8 to C.sub.18 fatty acids and their esters and amides thereof. The at least one acid-functionalized layer contains the at least one fruit acid in an amount of 2 wt. % to 30 wt. %, based on the total weight of the at least one acid-functionalized layer.

Systems for treatment of air are provided. In one embodiment, a system comprises a pre-filter layer, a smaller particle filtration layer, a carbon layer and a photocatalytic layer. Among the four layers, the pre-filter layer may be the furthest upstream in a direction of air flow, and the photocatalytic layer may be the furthest downstream in a direction of air flow.

Embodiments relate generally to a filter, for example, for attachment onto a gas detector device or a gas sensor, and attempt to improve the efficiency and service life of the filter. Embodiments typically comprise a dustproof membrane and a waterproof membrane. Some embodiments may also comprise a splash-proof cap and/or features to reduce negative pressure on the filters.

The present invention relates to the field of machines for cleaning, particularly vacuum cleaning devices. There is disclosed a filter cartridge for a vacuum cleaner comprising first and second opposite end walls, a side wall or walls which extend between the end walls so as to define an enclosure which surrounds a filter interior, wherein one or more of the walls comprises filter membrane material, the cartridge having an opening provided through the first end wall for receiving air-entrained detritus into the interior, the opening being defined by a rigid support structure which spans and supports the first end wall of the cartridge. The cartridge typically includes a non-return valve which closes when suction is removed so as to help prevent collected detritus escaping from the filter cartridge interior. The valve may comprise a conical valve with flexible facets, or a cantilever flap.

Devices, systems and methods are disclosed which relate to using a wet foam elution method for removal of particles from a flat filter. Particles are captured from the atmosphere onto the flat filter. The flat filter is then placed into an extractor which passes a stream of wet foam through the flat filter. Expansion of the foam works to efficiently remove captured particles. The foam flows from the filter along with the captured particles into a sample container. Once in the sample container, the foam quickly breaks down leaving an analysis ready liquid sample.

Embodiments provide a filter with a generally rectangular, non-cylindrical profile. The filter may have multiple pleat packs positioned between pleat covers that define regions and flow channels in a cavity of the filter body. The pleat covers have openings that allow a fluid to flow through the multiple pleat packs via parallel flows or series flows. End caps bonded to the body define flow passages for directing the fluid from an inlet to an outlet via the pleat packs for series or parallel filtration. The pleat packs may be made of the same or different materials and may be configured with the same or different heights based on flow requirements. A cage or a separator may be positioned between the pleat packs. The pleat packs may be made of a continuous pleated membrane with bridges defining a space between the pleat packs to accommodate the cage or separator.

A smoke and dust treatment apparatus for welding, said apparatus comprising a polishing and dust extraction module and a smoke and dust purification module. The polishing and dust extraction module comprises a double-layer dust extraction cover (3), a protective cover (2), an industrial brush (4), a first air guide portion, a second air guide portion (24) and a drive motor (22), the drive motor (22) driving the industrial brush (4) to rotate at high speed to perform polishing. During welding and polishing, a mechanical arm (6) drives the double-layer dust extraction cover (3), and a suction hole (20) of the double-layer dust extraction cover (3) and a suction guide hole (19) on the industrial brush (4) simultaneously take in toxic gas and debris such as iron filings.

A high-adsorption-performance nanofiber filter medium includes a support material and a composite nanofiber filtration layer that includes multiple nanometer composite nanofiber layers deposited and stacked on the support material. The nanometer composite nanofiber layer includes first, second, and third nano-powder composite nanofibers, which are uniformly mixed by means of an airflow or are sequentially laminated to form the nanometer composite nanofiber layer. The nanometer composite nanofiber layer formed through sequential lamination includes first, second, and third nanofiber layers. The first nanofiber layer includes multiple first nano-powder composite nanofibers. The second nanofiber layer is stacked on the first nanofiber layer and includes multiple second nano-powder composite nanofibers. The third nanofiber layer is stacked on the second nanofiber layer and includes multiple third nano-powder composite nanofibers. The composite nanofiber filtration layer is formed of multiple nanometer composite nanofiber layers, so that the high-adsorption-performance nanofiber air filter medium shows improved performance.

An electrostatic adsorption mask is provided. The mask comprises two straps, a mask body, a filtering layer and a tiny power. The filtering layer is located in the mask body and comprises a first carbon nanotube layer, a second carbon nanotube layer and an insulated porous layer. The insulated porous layer is located between the first carbon nanotube layer and the second carbon nanotube layer. The first carbon nanotube layer and the second carbon nanotube layer are electrically coupled with the tiny power. An electric field is existed between the first carbon nanotube layer and the second carbon nanotube layer.