How to choose the back-up bearing

In order to obtain high accuracy, high rigidity of the feed system, not only should choose high precision ball screw pair of high stiffness, and must attach great importance to the design of the ball screw bearing. Because of the ball screw is the main load of the axial load, radial load from the dead weight of horizontal screw, therefore, ball screw axial accuracy and high requirement of stiffness. For CNC carving and milling machine tool feed system requires flexible movement, the tiny displacement ( Screw tiny corner) Response is sensitive, so should choose high precision operation, high axial rigidity, small friction moment of rolling bearing. At present, all kinds of bearings used in most is 60 b contact Angle thrust angular contact ball bearings. CNC carving and milling machine tool using the angular contact ball bearing, bearing of 2 or more usually need combined, and exert pre-tightening force to use. The combinations are equipping back-to-back ( The DB) Equipping (face to face, DF) , serial piece together ( DT) 。 When using this kind of bearing on CNC carving and milling machine tool, in order to easy to absorb the ball nut with bearing between the coaxial degree, generally adopts DF group matching method.
at present, both at home and abroad of CNC engraving and milling machine> ball screw bearing bed design manufacturers have typical structure developed into the bearing composition unit. Bearing composition unit including bearings, bearing, seal and fasteners. Figure 1 has been developed for us design way of equipping face to face, DF) 60 b contact Angle thrust angular contact ball bearing series composition unit, its bearing aperture from & lt; 20 ~ < 50, the structural type of flange and the anchor type. CNC carving and milling machine tool the X, Y, two screw pairs combination of anchor bearing unit, and Z to screw pairs using flange bearing combination unit, thus formed the X, Y, Z three screw fixed on both ends of bearing. Figure 1

bearing composition unit
engraving machine price information in the numerical control network.