An air cleaner includes a case, an air inlet, an air outlet, a grill covering the air inlet to filter airborne oil droplets, a fan to suction air through the air inlet and discharge air out of the air outlet, a roll filter provided between the grill and the fan to filter oil mist, and a filter roller to cut the roll filter. The roll filter includes a roller and a filter sheet wound around the roller, and the filter sheet may be unwound to extend behind the grill. When the filter sheet becomes dirty, the roll filter is further unwound so that a clean section is provided behind the grill, and the filter cutter may cut off the dirty section. During cutting, a clamp holds down the filter sheet. The case includes a slit through which the dirty section of the filter sheet passes for discarding.

An air cleaner includes a case, an air inlet, an air outlet, a grill covering the air inlet to filter airborne oil droplets, a fan to suction air through the air inlet and discharge air out of the air outlet, a roll filter provided between the grill and the fan to filter oil mist, and a filter roller to cut the roll filter. The roll filter includes a roller and a filter sheet wound around the roller, and the filter sheet may be unwound to extend behind the grill. When the filter sheet becomes dirty, the roll filter is further unwound so that a clean section is provided behind the grill, and the filter cutter may cut off the dirty section. During cutting, a clamp holds down the filter sheet. The case includes a slit through which the dirty section of the filter sheet passes for discarding.

An apparatus for safely enabling air filtering by temporarily joining a box fan to a replaceable air filter includes: (a) an air chamber frame with a rear portion that is configured to accommodate the replaceable air filter, (b) a frame stabilizing means that includes a front mounting platform which is configured to temporarily hold a box fan that is oriented to pull air through the filter, (c) a gasket that is configured to attach to the frame's front surface and minimize air flow around the gasket and into the frame, (d) a vent door located in the frame and configured to open to allow air to enter the frame's interior region when the filter is clogged, (e) an alarm mechanism attached to the vent door and configured to provide a signal when the door is been opened, and (f) an alarm device configured to receive the alarm mechanism's signal and provide an alarm that the air filter needs replacement.

An air cleaner is provided that may include a main body having at least one cylindrical filter and at least one filter frame that forms a mounting space for the at least one filter; and a cylindrical case coupled to an outside of the main body, the cylindrical case having at least one suction inlet through which air is suctioned toward the at least one filter, so that air may be suctioned in 360-degree directions. If the cylindrical case is opened, the at least one filter may be extracted to the outside in a radial direction from the mounting space, thereby facilitating attachment/detachment of the at least one filter.

A filter device and a filter system are provided. A magnetic unit is disposed on at least one side of the filter device. The filter device includes a filter and a magnetic fixing device. The filter includes a first side wall. The magnetic fixing device includes a body, a clipping portion, and the magnetic unit. The body includes a top edge, a bottom edge, a first side face, and a second side face opposite to the first side face. The clipping portion includes a top flange extending from the top edge along the facing direction of the first side face by a first distance and a clip plate extending from an outer edge of the top flange toward the bottom edge by a second distance. The first side wall is clipped between the clip plate and the first side face. The magnetic unit is disposed on the second side face. The filter system includes a frame and the filter device.

An air purifier includes a ventilation cover, a filtering component, and a sterilization component. The ventilation cover has an air inlet and an air outlet. The filtering component is fixed at the air outlet. The sterilization component is disposed between the air inlet and the air outlet. An air ventilation device may include the air purifier.

A door for an air cleaner housing is disclosed. The door comprises a baseplate having a first side and a second side, a gasket attached to the first side of the baseplate, a backplate connected to the second side of the baseplate, and a front plate spaced apart from the backplate by spacers, wherein the baseplate, the backplate and the front plate are attached by a plurality of fasteners. Slots may be formed in the baseplate, and a magnet is positioned in each of the slots. The baseplate, the backplate, and the gasket dimensions may be adapted to fit within an opening in an air-cleaner housing. The magnets may be positioned to hold the door in position the housing opening. The gasket comprises a cellular urethane that seals the door to the housing to prevent air leaks.

An air cleaner includes a case, an air inlet, an air outlet, a grill covering the air inlet to filter airborne oil droplets, a fan to suction air through the air inlet and discharge air out of the air outlet, a roll filter provided between the grill and the fan to filter oil mist, and a filter roller to cut the roll filter. The roll filter includes a roller and a filter sheet wound around the roller, and the filter sheet may be unwound to extend behind the grill. When the filter sheet becomes dirty, the roll filter is further unwound so that a clean section is provided behind the grill, and the filter cutter may cut off the dirty section. During cutting, a clamp holds down the filter sheet. The case includes a slit through which the dirty section of the filter sheet passes for discarding.

An air cleaner includes a case, an air inlet, an air outlet, a grill covering the air inlet to filter airborne oil droplets, a fan to suction air through the air inlet and discharge air out of the air outlet, a roll filter provided between the grill and the fan to filter oil mist, and a filter roller to cut the roll filter. The roll filter includes a roller and a filter sheet wound around the roller, and the filter sheet may be unwound to extend behind the grill. When the filter sheet becomes dirty, the roll filter is further unwound so that a clean section is provided behind the grill, and the filter cutter may cut off the dirty section. During cutting, a clamp holds down the filter sheet. The case includes a slit through which the dirty section of the filter sheet passes for discarding.

An air cleaner includes a case, an air inlet, an air outlet, a grill covering the air inlet to filter airborne oil droplets, a fan to suction air through the air inlet and discharge air out of the air outlet, a roll filter provided between the grill and the fan to filter oil mist, and a filter roller to cut the roll filter. The roll filter includes a roller and a filter sheet wound around the roller, and the filter sheet may be unwound to extend behind the grill. When the filter sheet becomes dirty, the roll filter is further unwound so that a clean section is provided behind the grill, and the filter cutter may cut off the dirty section. During cutting, a clamp holds down the filter sheet. The case includes a slit through which the dirty section of the filter sheet passes for discarding.