A vacuum cleaner includes: an inlet pipe; and a lock mechanism that fixes an extension pipe, which is connected to the inlet pipe. The lock mechanism includes a pipe-lock lever, which has a pipe-hook part that is hooked into a pipe-recess part provided on the extension pipe. The pipe-lock lever also has a main-body part, which is disposed on an upper portion of the inlet pipe and on which the pipe-hook part is disposed, and one or more projection parts, which project(s) laterally from a side portion or side portions of the main-body part.

A gas valve (11) for ventilation which comprises a main body (12) having a first gas chamber (13), a second gas chamber (15) and at least an inlet duct (14) for supplying a gas to the first gas chamber (13). The gas valve (11) further comprises a proportional valve (24) for temporally sealing the first gas chamber (13) from the second gas chamber (15). The second gas chamber (15) comprises at least a second passage opening (22) for releasing the gas from the second gas chamber (15) and the second gas chamber (15) comprises a port (30) for connecting a pressure measurement apparatus for measuring the gas pressure in the second gas chamber (15). A circuit with a ventilation limb which comprises a gas valve (11) and a method for determining a releasing gas flow of a gas valve are also disclosed.

An air cleaner assembly can contain an air filter element to filter contaminant material out of an air stream. In some examples, the air cleaner assembly includes a housing with an integrated noise suppression chamber for supplying air to a downstream compressor. The housing forms a cavity into which an air filter element is inserted. Contaminated air enters the housing and passes through the air filter. Filtered air can discharge from the housing through a first opening supplying air to a combustion engine and a second opening supplying air to a compressor. Air supplied to the compressor passes from the interior of the housing containing the filter element and through the integrated noise suppression chamber before being discharged. The acoustic energy released by the filtered air stream exiting the air cleaner assembly may be reduced by passing through the noise suppression chamber.

Aspects of a sound-reducing air purification unit. In some units, the sound-reducing air purification unit can include a filter, a blower that causes air to flow through the filter and into an inlet of the blower, a sound reduction unit between the filter and an outlet, to absorb sound emitted by the blower, a discharge channel that channels the air expelled from the blower to a discharge grille, sound-reducing media positioned on either side of the discharge channel, to absorb sound emitted by the blower within the discharge channel, and a discharge grille that allows the air to flow from the discharge channel into the outlet.

A filter element is provided having a tubular shape defining an inner space, a first outlet in communication with the inner space and a second outlet in communication with the inner space, wherein the second outlet has an offset position in relation to the first outlet in a transversal direction of the filter element. Also provided is a filter housing having an inner housing space adapted to receive a tubular filter element, the filter housing having an inlet, a first outlet located in a first end of the filter housing, and a second outlet located in a second end of the filter housing, wherein the second end is located opposite to the first end in relation to the inner housing space.

An air purification device for purifying and recirculating air includes a housing, a filter mounted within the housing adjacent an inlet of the housing, a blower for drawing room air into the housing through the inlet, and an ionizer mounted at or adjacent both an exhaust portion of the blower and an outlet in the housing. Filtered air drawn into the housing by the blower is ionized immediately prior to being ejected from the housing. A silencer duct may be provided at the exhaust portion of the blower for mounting the ionizer and reducing noise.

An air purification-aromatherapy machine includes a housing, an aromatherapy assembly, a filter screen, and an air extractor; the housing is provided with an air inlet and an air outlet; the aromatherapy assembly, the filter screen and the air extractor are placed in the housing; the air extractor comprises a fan, an air duct configured for guiding an airflow blown by the fan to the air outlet, and a sound absorber configured for absorbing noise of the airflow; an end of the air duct is extended to the air outlet, the sound absorber is placed in the air duct and corresponding to the air outlet.

A humidification and air cleaning apparatus is provided, in which a wave having a predetermined cycle is formed on a plurality of blades of a blower fan, such that operating noise caused by a flow of discharged air may be minimized, and a wave is formed at a trailing edge, such that a phase difference may be formed for air to be separated, and air flow noise of the discharged air may be reduced.

The present disclosure generally relates to an air filtration system, an air filtration device, and an air filtration module for removing ultra-fine particles (UFPs), pathogens (e.g., viruses, bacteria, etc.), volatile organic compounds (VOCs), oxides or odors. The systems, devices, and filter modules of the disclosure perform at enhanced filter and power efficiencies. An air filtration system is provides that includes a docking base for receiving a removable, portable air filtration device in fluid communication with the docking base. In certain embodiments, the air filtration system further includes the removable, portable air filtration device. The portable air filtration device may optionally include an air filtration module.

An air cleaner of an internal combustion engine is provided with a first housing including an inlet, a second housing including an outlet, and a filter element located between the first housing and the second housing. A Helmholtz resonator is arranged inside the first housing. An upright wall projects from a bottom wall of the first housing toward the filter element and extends in an axial direction of the inlet. The upright wall forms a chamber of the Helmholtz resonator. A noise-absorption region is defined by the upright wall, a side wall of the first housing, the bottom wall, and the filter element. The noise-absorption region leads to the inlet and extends in the axial direction.