Page 41 - needle bearings

Bearing Fits
Shaft and Housing Design
NTN
NTN

(1) Inner ring
For fixing inner ring correctly on a shaft, the shaft
shoulder face is finished at the right angle against the
shaft axial center and, in addition, the shaft corner is
rounded smaller than the inner ring chamfer dimension.
Where the corner roundness ra max must be made
larger for specific shaft strength (Fig.7.4a) or the shaft
shoulder is low (Fig. 7.4b), a spacer must be inserted
between the shaft shoulder and the inner ring to hold a
full contact surface with the inner ring. Furthermore, for
facilitating inner ring pull-out work the shaft shoulder is
provided with a notched groove,as illustrated in Fig. 7.5,
to accept an inner ring pull-out jig (puller).
Fig. 7.6 Inner ring fixing by snap ring
NTN snap ring WR type for shaft use (Refer to
Dimensions Table on page B-227) can be used for simply
fixing inner ring in axial direction. (Fig. 7.6) Moreover,
inner ring can be fixed in axial direction using an end
plate or a side ring as illustrated in Figs. 7.7 and 7.8.

Fig. 7.7 Inner ring fixing by end plate
ra max

rs min rs min
ʢaʣ ʢ bʣ

Fig. 7.4 Inner ring fixing by use of spacer

Fig. 7.5 Inner ring pull-out jig(puller) Fig.7.8 Inner ring fixing by side ring

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