Attendance

Bearings

Permit constrained linear or rotary motion between parts. Keep shafts stable and help machines run smoothly.
Bearing types

• Radial (rotary)
• Thrust (linear/axial)

Anatomy of a ball bearing

• Outer race
• Inner race
• Balls/rolling elements
• Cage/separator

Interactions: housing and shaft
Sliding bearings (plain, journal, bushing, sleeve)

• Could be as simple as drilling a hole in a block of wood

Bushings vs. Bearings?
Radial bearing types

• Caged
• Full complement
• Angular contact

Thrust bearing types

• Ball
• Roller, needle roller

Special bearing types

• Tapered roller
• Spherical
• Crossed roller

Bearing construction

• The housing holds the outer race
• The shaft can constrain the inner race
• Normally, rotating ring is a tighter fit
• Choose bearing and shaft together:

Ordering bearings Almost any general parts store will have them. Check out Electric Motor Trading on Canal.

• Some bearings are ABEC (Annular Bearing Engineers Committee ) rated
• The higher the number, the better the bearing
• Only need to pay attention to in high speed, long life designs
• Order based on load rating 1st, size 2nd

Guest Speaker: Eric Singer of LEMUR