A shaft is to be designed to support the spur pinion and helical gear shown in the figure on two bearings spaced 700 mm center-to-center. Bearing A is a cylindrical roller and is to take only radial load; bearing B is to take the thrust load of 900 N produced by the helical gear and its share of the radial load. The bearing at B can be a ball bearing. The radial loads of both gears are in the same plane, and are 2.7 kN for the pinion and 900 N for the gear. The shaft speed is 1200 rev/min.

Find::

1.Perform a force analysis to find the bearing reaction forces.

2.Draw shear and bending moment diagrams.

3.Determine the critical locations for stress design.

Given::

1.A torque of 740 kN-mm is transmitted by the shaft.

2.The diameters of the pinion and gear are 200 mm and 300 mm, respectively.

3.The diameter of shaft is 76 mm.

4.The design factor is chosen in the range 1.5-2.5

5.The material is ANSI 1050.