A method includes providing a bearing housing configured to house a bearing, the bearing housing enclosing a free volume for receiving lubricant, providing a quantity of the lubricant in the free volume, and providing a sensor configured to measure at least one parameter affecting a degradation rate at which the lubricant will degrade and to produce at least one output signal indicative of the measured at least one parameter. The method also includes providing a pump for pumping lubricant into the bearing housing, providing a controller configured to receive the at least one output signal from the sensor and configured to control the pump based the received at least one output signal, and controlling the pump based on a function of the received at least one output signal.

A grease composition containing base oil, a thickener, and an additive, wherein said additive contains at least one kind selected from among a phosphite ester shown by a chemical formula (1) or a phosphite ester shown by a chemical formula (2); a content of said phosphite ester is 0.5 to 4 parts by weight for 100 parts by weight which is a total of an amount of said base oil and that of said thickener; and said additive contains neither phosphite esters other than said phosphite ester shown by said formula (1) or by said formula (2) nor phosphate esters having organic groups whose carbon number is not less than three:

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A grease inhibitor is disposed about a rotating shaft of an electric machine. The grease inhibitor is configured to inhibit flow of grease towards electromagnetic components of the electric machine along the shaft. The grease inhibitor includes an inner member that rotates with the shaft and that interfaces with a static component to form the grease inhibiting interface.

A bearing arrangement having a bearing mounted in a housing, wherein a grease lubricant is present within the housing for lubricating the bearing, a support frame at least partly made of an electrically insulating material, arranged in a space within the housing that lies axially between the bearing and a housing seal. The support frame includes at least one electrode pair having first and second electrodes arranged to enable grease lubricant to contact therewith. A capacitance meter provided for measuring a capacitance between the first and second electrodes. The support frame provides a radially oriented surface and a plurality of ribs that extend in a radially inward direction, the ribs having sufficient circumferential spacing to enable grease to flow between adjacent ribs. One of the first and second electrodes is provided on the radially oriented surface of the support frame or on a rib surface that faces an adjacent rib.

A bearing device is constituted by a rolling bearing and a lubricant supply device combined with each other. The lubricant supply device includes a lubrication oil tank which stores pressurized lubrication oil and has a lubrication oil discharge spout; an open/close valve which opens/closes the lubrication oil discharge spout of the lubrication oil tank; a driving section which operates the open/close valve; and an electric power source section which generates electric energy for operation of the driving section. The lubricant supply device is attached to the rolling bearing or to a spacer adjacent thereto.

A bearing system includes a housing having an interior that is configured to contain a quantity of grease or oil, a bearing mounted in the interior of the housing, and a system for introducing an inert gas into the interior of the housing. The inert gas is preferably substantially oxygen free so as not to oxidize the grease or oil.

A method of operating a lubrication system for lubricating a bearing in a housing includes the following steps: dispensing a quantity of lubricant within the bearing housing; monitoring a containment period of time during which the lubricant quantity is contained within the housing; determining when the containment time period exceeds a predetermined value of time; and dispensing another quantity of lubricant within the bearing housing when the containment time period exceeds the predetermined time value such that the other quantity of lubricant displaces the quantity of lubricant from the bearing housing.

A lubricant supply unit that supplies lubricating oil to a raceway groove of an inner ring is fixed to an outer ring. The lubricant supply unit is provided with a first and second radially separated electrodes used to supply electric power from an external power source to the micropump. Each of the first and second radially separated electrodes is fixed to an outer face of a tank that is stationary relative to the micropump so as to be exposed on the outside of the lubricant supply unit. The first radially separated electrode is arranged so as to be apart from the second radially separated electrode.

A bearing arrangement is provided having a bearing mounted in a housing, wherein a grease lubricant is present within the housing for lubricating the bearing. The arrangement further provides a support frame made of an electrically insulating material, arranged in a space within the housing between the bearing and a housing seal. The support frame is provided with at least one electrode pair having first and second electrodes arranged such that a portion of the grease lubricant is located between the first and second electrodes. A capacitance meter is provided for measuring a capacitance between the first and second electrodes. The first and second electrodes of the at least one electrode pair are provided on a radially oriented surface of the support frame, which surface is arranged such that the grease is able to move in an axial direction over the surface.

A bearing system includes a bearing housing configured to house a bearing, the bearing housing enclosing a free volume for receiving lubricant, a quantity of the lubricant in the free volume, a sensor configured to measure at least one parameter affecting a degradation rate at which the lubricant will degrade and to produce at least one output signal indicative of the measured at least one parameter, a pump for pumping lubricant into the bearing housing, and a controller configured to receive the at least one output signal from the sensor and to control the pump based a function of the received at least one output signal.