Machine Design First 15

Three extension springs are hooked in series that support a single weight of 100 kg. The first spring is rated at 4 kN/m and the other two springs are rated 6 kN/m each. Determine the equivalent stiffness of the three springs.

Three extension springs are hooked in parallel that support a single weight of 100 kg. The springs are rated 4 kN/m, 5 kN/m, and 6 kN/m, respectively. Determine the equivalent spring constant of the three spring

A 36-tooth pinion turning at 300 rpm drives 120-tooth gear of 14.5o involute full depth pressure angle. Determine the rpm of the driven gear.

If two parallel shafts are connected by cylinders in pure rolling contact and turning in the same direction, and having a speed ratio of 2.75, what is the Center distance of the two shafts assuming that the diameter of the smaller cylinder is 22 cm?

A triple-thread worm has a lead angle of 17o and a pitch diameter of 2.2802 inches. Find the center distance when the worm is mated with a wheel of 48 teeth

A double-thread worm has a pitch diameter of 3 inches. The wheel has 20 teeth and a pitch diameter of 5 inches. Find the gear helix angle.

A right-handed single-thread hardened-steel worm has a catalog rating of 2.25 kW at 650 rpm when meshed with a 48-tooth cast-steel gear. The axial pitch of the worm is 25 mm, normal pressure angle is 14.5o , and the pitch diameter of the worm is 100 mm. The coefficient of friction is 0.085. Determine the shafts center distance.

A 20o straight-tooth bevel pinion having 14 teeth and a diametral pitch of 6 teeth/inch drives a 42-tooth gear. The two shafts are at right angles and in the same plane. Find the pitch angle of the pinion.

A parallel helical gear-set consists of a 19-tooth pinion driving a 57-teeth gear. The pinion has a left-hand helix angle of 20o , a normal pressure angle of 14½o , and a normal diametal pitch of 10 teeth/inch. If the pinion is to transmit 50 Hp at a speed of 1750 rpm. Determine the center distance of the two gears.

What modulus of elasticity in tension is required to obtain a unit deformation of 0.00105 from a load producing a unit tensile stress of 3163.27 kg/cm2 ?

A disc clutch has 6 pairs of contacting friction surfaces with an outside diameter of 200 mm and an inside diameter of 100 mm. The coefficient of friction of the clutch materials is 0.4 and the axial force is 1500 N. The shaft speed is 1200 rpm. Determine the Hp that can be transmitted by the clutch assuming uniform pressure.

Determine the power capacity of a cone clutch under uniform pressure and assuming the following conditions: major diameter = 250 mm; minor diameter = 200 mm; length of conical elements in contact = 125 mm; rotational speed = 870 rpm; coefficient of friction = 0.30; and allowable pressure = 70 kPa.

A flywheel has a mean diameter of 4 ft and is required to handle 2250 ft-lb of kinetic energy. It has a width of 8 inches, mean operating speed is 300 rpm and the coefficient of fluctuation is to be 0.05. Find the weight of rim, assuming that the arms and hub are equivalent to 10 % of the total rim weight. The flywheel is made up of cast iron with specific weight of 0.26 lb per cubic inch.

A 20o involute spur gear has a tooth whole depth of 16.95 mm, a tooth thickness of 13.2 mm, and a pitch of 3. Determine the circular pitch of the gear.

A vertical steel cylinder water tank is 30 m in diameter and 45 m high. The allowable stress of the steel plate is 1224 kg/cm2 . Without reinforcing angle bars and rods, what is the thickness of the steel plate?