Bearing unit and speed reducer-equipped motor

A bearing unit, comprising:

• a thrust damper extendable in an axial direction of a shaft placed in a gearbox, the movement of which toward one side in the axial direction is regulated;
• a shaft receiver component held by the thrust damper on the other side of the thrust damper in the axial direction;
• a metal holder that holds the shaft receiver component in such a manner as to be detachable in the axial direction;
• and
• an oilless metal held by the metal holder and placed on the other side of the shaft receiver component,
• wherein the thrust damper, the shaft receiver component, the metal holder, and the oilless metal are integrated all together before being incorporated into the gearbox,
• the metal holder includes a press-fit end portion press-fitted and fixed in a storage portion of the gearbox, and
• the shaft receiver component is light press-fitted in the metal holder before being incorporated into the gearbox, is pressed toward the one side by the shaft after being incorporated into the gearbox to terminate a light press-fitted state in the metal holder, and is held in such a manner as to be slidable in the axial direction relative to the metal holder.