mech 153 - assignment 5

The figure shows the cross-section of a 2-speed manual transmission gear system.

Speed is increased and decreased by sliding the gear sub-assembly that makes up gears D & C, back and forth along the countershaft.  When the C/D slider sub-assembly is in the position shown, power comes into the input shaft, passes through gear A to gear B, then along the counter shaft, up gear D to gear F and finally out the output shaft.  To change the output speed the gear system is first stopped.  Then the C/D slider sub-assembly is moved to the left, along the countershaft, until gears D and F disengage and gears E and C engage.  The gear system is then restarted and the output shaft turns at a new speed.

Your job is to figure out a number of important design numbers.

1. The speed and direction of the output shaft and countershaft give a certain input speed.  Fill in the speed table below.
2. Determine the maximum power that can be transferred through the gear system.
3. Will each of the gears fit onto the shafts indicated?
4. Are the shaft centre-to-centre shaft distances shown on the drawing correct?  Confirm them and correct if necessary.

Note: Make sure you clearly show all calculations and text table references.