To provide a grease composition that is capable of effectively preventing an early-flaking caused by hydrogen embrittlement, and a grease-sealed bearing in which the grease composition is sealed. A grease composition 7 contains a base oil, a thickener, and an additive. The additive contains sodium molybdate, and zinc alkyldithiophosphate having a 1-30 C primary alkyl group. The grease composition contains 0.1-5 mass % of the sodium molybdate relative to the whole of the grease composition. The grease composition contains 0.1-5 mass % of the zinc alkyldithiophosphate relative to the whole of the grease composition.

Provided in one embodiment of the present invention is a bearing assembly comprising: an outer ring in which a hollow is formed and which has a protrusion protruding toward a central direction along the inner circumferential surface and a first ball contact portion and a second ball contact portion that are formed by the protrusion;

an inner ring having a third ball contact portion on the outer circumferential surface and forming a first track portion and a second track portion by being inserted into the hollow; and at least one bearing ball disposed between the outer ring and the inner ring to rotatably connect the outer ring and the inner ring, wherein the bearing balls are arranged in multiple rows in the first track portion and the second track portion and are configured to contact each of the ball contact portions.

Provided in one embodiment of the present invention is a bearing assembly comprising: an outer ring in which a hollow is formed and which has a protrusion protruding toward a central direction along the inner circumferential surface and a first ball contact portion and a second ball contact portion that are formed by the protrusion;

an inner ring having a third ball contact portion on the outer circumferential surface and forming a first track portion and a second track portion by being inserted into the hollow; and at least one bearing ball disposed between the outer ring and the inner ring to rotatably connect the outer ring and the inner ring, wherein the bearing balls are arranged in multiple rows in the first track portion and the second track portion and are configured to contact each of the ball contact portions.

A gas turbine engine including a compressor that compresses air taken in; a combustor that sprays a fuel into the compressed air and combusts the fuel; a turbine rotated by energy of the combustion gas generated by the combustor; a rotating shaft coupling the compressor and the turbine; a rear bearing that is a cageless ball bearing including an inner race, an outer race, and a ball, the inner race being fixed to a portion of the rotating shaft which portion is close to the turbine; a housing to which the rear bearing is attached; and a rear bearing holding member that is interposed between the rear bearing and the housing and holds the outer race of the rear bearing such that the outer race of the rear bearing is movable in an axial direction relative to the housing.

Provided is a method and a system capable of detecting a fatigue state before damage to a rolling bearing component occurs, and capable of performing diagnosis of the fatigue state without having to disassemble the rolling bearing.

A magnetic sensor arranged close to a component of a rolling machine element measures magnetic flux density in the axial direction and/or radial direction of the component, then the amount of change in magnetic flux density is calculated based on a reference magnetic flux density corresponding to the magnetic flux density before the start of use of the component, and the progression of fatigue of the rolling machine element is determined from the amount of change.

The invention provides a pump unit for a miniature cleaning machine, and belongs to the technical field of cleaning machines. The problem that an existing pump unit is frequently maintained is solved. The pump unit for the miniature cleaning machine comprises a motor, a pump shell, a plunger and a transmission assembly, the plunger and the transmission assembly are arranged in the pump shell, a reset spring enabling the plunger to always have the upward moving trend is arranged in the pump shell, the transmission assembly comprises a pump main shaft, an eccentric shaft and a ball bearing, one end of the pump main shaft is in transmission connection with the motor, and the other end of the pump main shaft is in transmission connection with the eccentric shaft. The other end of the pump main shaft is in transmission connection with one end of the eccentric shaft, the other end of the eccentric shaft is connected to the pump shell, the eccentric shaft is sleeved with the ball bearing, and a peripheral face of the ball bearing is attached to an upper end face of the plunger. The structure solves the problem of frequent maintenance of the pump unit.

A bearing assembly comprises ring assemblies cooperating to form a roller volume. A single circumferential slot is in an inner circumferential surface of the inner ring assembly and in fluid communication with the roller volume through central passages in the inner ring assembly. The proximal inner ring includes proximal axial slots extending axially along a proximal portion of the inner circumferential surface, a first plurality of the proximal axial slots being in fluid communication with the roller volume, a second plurality of the proximal axial slots not in fluid communication with the roller volume. The distal inner ring includes distal axial slots extending axially along a distal portion of the inner circumferential surface from the circumferential slot to respective distal passages in fluid communication with the roller volume, wherein a circumferential spacing between adjacent proximal axial slots is equivalent to a circumferential spacing between adjacent distal axial slots.

A ball bearing assembly device includes: an inner and outer ring holding unit which holds an outer ring and inner ring in a state where an outer ring raceway surface and inner ring raceway surface are eccentric to each other on a same plane so as to form a gap space; a stocker; a robot arm; a ball holding mechanism which is disposed at a tip of the robot arm; and a control unit. The control unit controls the ball holding mechanism to hold any ball from the stocker, controls the robot art to transport the held ball to a ball insertion position in the gap space corresponding to a kind of ball bearing, and inserts the held ball into the gap space, which are repeated by the number of balls of the ball bearing.

A ball bearing assembly device includes: an inner and outer ring holding unit which holds an outer ring and inner ring in a state where an outer ring raceway surface and inner ring raceway surface are eccentric to each other on a same plane so as to form a gap space; a stocker; a robot arm; a ball holding mechanism which is disposed at a tip of the robot arm; and a control unit. The control unit controls the ball holding mechanism to hold any ball from the stocker, controls the robot art to transport the held ball to a ball insertion position in the gap space corresponding to a kind of ball bearing, and inserts the held ball into the gap space, which are repeated by the number of balls of the ball bearing.

A camera module includes a housing, a carrier, a frame, a lens holder, an autofocusing (AF) ball bearing, and an optical image stabilization (OIS) ball bearing. The carrier is coupled to the housing and configured to move in an optical axis direction. The frame is coupled to the carrier and configured to move in a first axis direction, perpendicular to the optical axis direction. The lens holder is coupled to the frame and configured to move in a second axis direction, perpendicular to the optical axis and the first axis. The AF ball bearing is disposed between the housing and the carrier. The OIS ball bearing is disposed on either one or both of the carrier and the frame, and the frame and the lens holder. Either one or both of the AF ball bearing and the OIS ball bearing have an elastic modulus of 20 GPa or less.