Annular and shaft oil dispensers

An annular-shaped oil dispenser having a central void through which a shaft is received, comprising:

• an outer circumferential surface;
• an inner circumferential surface concentrically disposed within the outer circumferential surface to define a central void along an axis of symmetry;
• an annular-shaped reservoir defined within a cross-sectional area between the outer circumferential surface and the inner circumferential surface, wherein said reservoir is enclosed by lateral walls;
• a fill port comprising an internal channel extending through a cross-section of the body from the reservoir to an outer surface of the annular-shaped oil dispenser, wherein a valve is connected within the fill port to allow in a gas external to the dispenser, thereby preventing a vacuum from building inside the annular-shaped oil dispenser as oil is dispensed;
• an outlet for dispensing oil from the reservoir, the outlet comprising an internal channel extending through the cross-section of the body from the reservoir to the outer surface of the annular-shaped oil dispenser, wherein at least one element from a group consisting of:
• a valve, a porous media element, a nozzle, a restrictor, a rupture disc, or a pressure compensated flow regulator is attached inside the outlet;
• a bearing mounted on the shaft, the bearing having a central void;
• wherein when the annular-shaped oil dispenser is mounted on the shaft said inner circumferential surface is in direct contact with an outer surface of the shaft, the central void of the oil dispenser is coaxially aligned with the central void of the bearing to allow lubricating oil dispensed from the outlet to flow into a channel of the bearing.