Page 9 - needle bearings

Classification and Characteristics of Bearings
NTN

Needle roller and cage assembly for small end
¡Strong impact load acts on this bearing and it
oscillates at high speed. Therefore, the cage bore
surface is finished with high precision so as to secure
lightweight, high rigidity and proper guide clearance.
¡The cage is made of high tensile special steel and its
surface is hardened ideally.
¡The cage is of bore guide type and the guide surface
is designed as long as possible to thereby reduce the
surface pressure.
¡The roller length is designed to the possible
maximum value against the connecting width and a
number of small-size needle rollers are fitted in the
cage to minimize the contact pressure.

Drawn-cup needle roller bearing

This bearing comprises an outer ring and needle
rollers, which were both drawn from special thin steel
plate by precision deep drawing, and a cage intended
to guide precisely the needle rollers.
¡This bearing is the type of the lowest section height,
of the rolling bearings with outer ring, best-suited to
space-saving design.
¡A hardened and ground shaft or inner ring (IR Series)
is used as the raceway.
¡This bearing needs no axial locking due to easy
installation and press-fit in the housing.
¡The close end type to close shaft end is available in
addition to the open end type.
¡Furthermore, the type with seal fitted in at single side
or double sides is also available.
¡The standard type comprises a needle roller and
cage assembly. In addition to this type, special type
comprising full complement rollers is available at
option.

Machined-ring needle roller bearings
This bearing type comprises a machined outer ring
and machined needle rollers, and a cage to guide
properly the needle rollers.
In the case of this bearing, the cage or the needle
rollers are guided by the ribs of the outer ring or the
face ring. Hence, this bearing is non-separable type. In
addition, the type with no inner ring is also available for
enabling a shaft to be used as the raceway surface. (Of
course, the type with inner ring is available.)
¡Selectively available for both of the metric system
and the inch system.
¡Best-suited to space-saving design due to its low
section height, then having the large load capacity.
¡High rigidity and high bearing accuracy due to its
machined (precut) outer ring
¡can be used with a housing made of light metal, etc.
due to its outer ring of high rigidity.
¡Outer ring with lubrication hole and lubrication groove
¡Single row and double row types available.
¡The type with seal fitted in at single side or double
sides is also available.

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