Provided is a linear compressor. The linear compressor includes a cylinder disposed in a shell to define a compression space for a refrigerant, a piston installed to reciprocate in the cylinder, a motor assembly that allows the piston to move in an axial direction of the cylinder and thereby to compress the refrigerant introduced into the compression space, a nozzle which is provided in the cylinder and through which a portion of the refrigerant introduced into the compression space passes, and a cylinder filter installed in the cylinder and disposed at an inlet-side of the nozzle. At least one or more surfaces of the cylinder filter are oil-repellent coated.

A compressor includes a cylinder comprising a cylinder body which has a cylindrical shape and defining a compression space for refrigerant gas, a piston configured to be reciprocated in an axial direction within the cylinder body and to compress the refrigerant gas in the compression space, and a frame in which the cylinder is received, the frame defining a gas hole, one side of the gas hole communicating with outside so that the refrigerant gas is introduced, the other side of the gas hole extending up to an inner circumferential surface so as to guide the refrigerant gas.

The present disclosure relates to reciprocating compressor. The present invention can prevent friction loss or abrasion between a cylinder and a piston, which is caused when a hydraulic bearing is blocked with a foreign substance, by preventing the foreign substance mixed in refrigerant gas from flowing into the hydraulic bearing, and can improve compressor performance by preventing a specific volume in a compression space from increasing when high-temperature refrigerant gas discharged in the compression space is cooled, such that vibration noise of the compressor can be reduced since a gas guiding part offsets vibration and the noise generated when a refrigerant is discharged in the compression space. Furthermore, the number of vibrations of a mover is increased and a driving operation for removing foreign substances is carried out to increase the number of vibrations of a cylinder such that any foreign substance stuck in a gas hole can be cleaned, thereby increasing performance and reliability of the compressor.

A method is disclosed that includes determining a current level of a plurality of lubricant parameters present in a portion of lubricant, comparing the current level of each of the plurality of lubricant parameters to a threshold value corresponding to each of the plurality of lubricant parameters, analyzing a priority of each of the lubricant parameters, and determining a health status of the lubricant in response to the comparing and the analyzing.

A method is disclosed that includes determining a current level of a plurality of lubricant parameters present in a portion of lubricant, comparing the current level of each of the plurality of lubricant parameters to a threshold value corresponding to each of the plurality of lubricant parameters, analyzing a priority of each of the lubricant parameters, and determining a health status of the lubricant in response to the comparing and the analyzing.

This blower apparatus includes an air blowing portion including a plurality of flat plates arranged with an axial gap defined between adjacent ones of the flat plates; a motor portion arranged to rotate the air blowing portion; and a housing arranged to house the air blowing portion and the motor portion. The housing includes an air inlet and an air outlet. At least one of the flat plates includes a plurality of through holes each of which is arranged to pass therethrough in the axial direction. An air flow traveling radially outward is generated between the flat plates by viscous drag of surfaces of the flat, plates and a centrifugal force. Since the air flow is generated between the flat plates, the air flow does not easily leak upwardly or downwardly.

This blower apparatus includes an air blowing portion including a plurality of flat plates; a motor portion; and a housing. The housing includes an air inlet and an air outlet. Each of a top flat plate and intermediate flat plates among the flat plates includes an air hole and an air blowing region radially outside of the air hole. Since the air flow is generated between the flat plates, the air flow does not easily leak upwardly or downwardly, and thus, an improvement in air blowing efficiency is achieved. A radial middle of the air blowing region of at least one of the intermediate flat plates is arranged radially outward of a radial middle of the air blowing region of an upwardly adjacent one of the flat plates.

This blower apparatus includes an air blowing portion, a motor portion, and a housing. The housing includes an air inlet and an air outlet. The air blowing portion includes a plurality of flat plates arranged with an axial gap defined between adjacent ones of the flat plates; and a spacer arranged between the flat plates. A rotating portion of the motor portion includes a hub including a flat plate holding portion arranged to hold at least one of the flat plates. An air flow is generated between the flat plates by viscous drag of surfaces of the flat plates and a centrifugal force. With the spacer being arranged between the flat plates, the axial gap can be adjusted. Since at least one of the flat plates is held by the flat plate holding portion, the air blowing portion is able to stably rotate.

A system and method for operating a fuel-cell system, which is attached to at least one further component via a cooling and/or lubricating circuit. A water-based, oil-free coolant and lubricant is used, and a flushing procedure for the fuel cell is initiated when a contamination of the fuel cell by the water-based, oil-free coolant and lubricant is detected.

A system and method for operating a fuel-cell system, which is attached to at least one further component via a cooling and/or lubricating circuit. A water-based, oil-free coolant and lubricant is used, and a flushing procedure for the fuel cell is initiated when a contamination of the fuel cell by the water-based, oil-free coolant and lubricant is detected.