Electric Shaft Bearings

Electric Shaft Bearings

A bearing ring is a device that contains numerous balls (or balls and rollers). Internal clearance is basically the distance one bearing ring moves radially or axially relative to another, usually at a right angle to each other. It's the clearance from the axle to the ring that determines its useful life span. The higher this clearance, the better the performance and life of the bearing, as a high clearance means that the bearing has less friction and hence more reliable performance.

Bearings are usually made of steel or cast iron; however, there are also many aluminum and copper varieties available these days, which are often cheaper. Bearings are mounted on the inner ring of a roller cage with the external rollers positioned on the face of a special bearing rod. They need to be very carefully aligned in order to provide a smooth bearing path and very low insertion forces. The external rollers can also be locked to reduce unwanted thrust loads.

When selecting a deep groove ball bearing it is important to select ones with a high compressive force rating and/or long life.The design of a shaft is also important; a shaft with a short throw angle will not have the same effect as one having a longer throw angle. Bearings may also have different gear ratios. This is important when selecting a bearing for an electric motor driving a saw blade. The best electric shafts would have gear ratios of two to four to allow for zero torque at the transmission location.