The 20-tooth pinion of Problem 15.20 rotates 210 rpm. Determine graphically the sliding velocity between the teeth
(a) at the start of contact,
(b) at the pitch point, and
(c) at the end of contact. Make vectors large enough to be scaled accurately.
Problem 15.20
A pair of mating spur gears with 6-mm modules and 0.35-rad pressure angles have 30 and 60 teeth.
(a) Make a full-size drawing of the tooth contact region, showing (and labeling)
(1) both pitch circles,
(2) both base circles,
(3) both root circles,
(4) both outside circles,
(5) pressure angle,
(6) length of path of contact,
(7) both angles of approach, and
(8) both angles of recess.
(b) Using values scaled from your drawing, state or calculate numerical values for
(1) length of path of contact,
(2) angles of approach,
(3) angles of recess, and
(4) contact ratio.