A filter housing of a fluid filter has a housing body with inlet and outlet openings for fluid. The housing body has an element receptacle for a filter element that separates inlet opening from outlet opening. The housing body has an installation opening providing access to the element receptacle in an installation direction and enabling insertion of the filter element into the element receptacle. The installation opening is arranged at a transverse side of the housing body laterally relative to a housing axis that is transverse to the installation direction. A housing cover closes off the installation opening. The housing body has a sealing surface contacting a seal of the filter element when inserted in the element receptacle and surrounding the housing axis at least partially circumferentially. A fall-out protection device prevents the filter element from falling out of the element receptacle when the installation opening is open.

A nitric oxide generator generates nitric oxide from a mixture of nitrogen and oxygen such as air treated by a pulsating electrical discharge. The desired concentration of nitric oxide is obtained by controlling at least one of a frequency of the pulsating electrical discharge and duration of each electrical discharge pulse.

An air cleaning system can rapidly senses occurrence of local pollution, caused by fine dust, through a remote sensor hub and supplies purified air to a polluted area in a concentrated manner, thereby quickly purifying indoor air.

There are provided a sensor substrate and a sensor device which have high detection accuracy. A sensor substrate includes an insulating substrate; sensing electrodes disposed in the insulating substrate, the sensing electrodes being columnar and being composed of at least one pair of positive and negative sensing electrodes, in the at least one pair of positive and negative sensing electrodes, part of a positive electrode and part of a negative electrode being each exposed from one surface of the insulating substrate; and innerlayer wiring lines embedded within the insulating substrate, the innerlayer wiring lines corresponding to the positive electrode and the negative electrode, respectively, in the at least one pair of positive and negative sensing electrodes.

A nitric oxide generator generates nitric oxide from a mixture of nitrogen and oxygen such as air treated by a pulsating electrical discharge. The desired concentration of nitric oxide is obtained by controlling at least one of a frequency of the pulsating electrical discharge and duration of each electrical discharge pulse.

A filter system with self-cleaning function and a clothes dryer using the filter system, wherein the filter system comprises a shell 5 with an air inlet 12 and an air outlet 13, a filter system screen 7, a cleaning unit 3, a driving device and a lint collection drawer 8, wherein the driving device includes a drive motor 1 disposed on the outer wall of the shell 5 and a screw rod 2 disposed inside the shell 5, the output shaft of the drive motor 1 passes through the small hole I 14 opened on the shell 5 and extends inside the shell; one end of the screw rod 2 is engaged with the output shaft of the drive motor 1 and the other end of the screw rod 2 is mounted inside the small hole II 15 opened on the wall of the shell 5 opposite to the output shaft of the drive motor. The cleaning unit 3 is screwed on the screw rod 2 and driven by the screw rod 2 to move back and forth and the lower end of the cleaning unit 3 is in contact with the filter system screen 7, and the automatic self-cleaning lint function could be achieved. For the clothes dryer, the overall structure becomes more compact and reliable by improving structure of the filter system, and the lint collection efficiency and also drying efficiency are increased.

A nitric oxide generator generates nitric oxide from a mixture of nitrogen and oxygen such as air treated by a pulsating electrical discharge. The desired concentration of nitric oxide is obtained by controlling at least one of a frequency of the pulsating electrical discharge and duration of each electrical discharge pulse.

A nitric oxide generator generates nitric oxide from a mixture of nitrogen and oxygen such as air treated by a pulsating electrical discharge. The desired concentration of nitric oxide is obtained by controlling at least one of a frequency of the pulsating electrical discharge and duration of each electrical discharge pulse.

An air filter apparatus includes at least one frame that is configured to receive a filter media, and at least one sensing mechanism for sensing contamination of the filter media. The sensing mechanism can include a wave emitter and a wave detector. The wave emitter and the wave detector can be arranged so that the wave travels along a path that is substantially parallel to outer faces of the filter media. The wave detector can be located at a first edge of the frame, and the wave emitter can be located spaced apart laterally from the wave detector at a second edge of the frame, so that waves from the emitter can travel along the path through and laterally across the filter media towards the detector. The path can be substantially perpendicular to the general direction of air flow within the filter media.

According to the present disclosure, air cleaner assemblies, housings, serviceable filter cartridges and features, components, and methods, relating thereto are disclosed. In general, the features relate to systems that are configured to aid in inhibiting an improper cartridge from being installed in an air cleaner housing, during servicing. A variety of features are characterized, and in many examples, the cartridge includes a seal arrangement having radially directed seal surface with at least a first non-wavy or non-projection/recess section and a second wavy or projection/recess section. Examples are shown and described in detail.