Question

The bevel pinion rotates at 840 rpm in the direction shown and transmits 5.25 kW to the gear. The mounting distances, the location of all bearings, and average pitch radii of the pinion and gear are shown in the figure. 231 I105 126 a) Calculate the forces for bevel gears b) Calculate the bearing forces c) From a bearing catalogue which is released by a bearing company (SKF, Schaeffler, Timken,...) select the suitable bearings. (D - C identical, A- B identical) 105 B 315

Answer 1

N=840 RPM

P=5.25KW

(a) Forces for bevel gears

     $\omega$=2$\Pi$N/60= (2$\Pi$*840)/60= 87.96 rad/s

    T=P*$\omega$= 5.25*87.96= 461.79Nm

   F(smaller gear)=T/r₁= 461.79/52.5= 8.796 N

   F(larger gear)= T/r₂=461.79/157.5= 2.932 N

(b) Work done on each bearing of the larger gear

       W=F(larger)* s = 2.932* [(126+84)/2-51]= 158.328 J

      Work done on smaller gear's bearing

      W=F(smaller)* s= 8.796* (105/2)= 461.79 J

(c) After checking the SKF catalogue, roller and ball bearings are most suitable ones.