A gearing system as shown in Figure Q3.2 is used to reduce the rotational speed 3000...

  

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A gearing system as shown in Figure Q3.2 is used to reduce the rotational speed 3000 rpm of the motor to 300 rpm at the output shaft.If diametral pitch of the gear is P = 10 in ¹ is used for all the gears (G2 to G5) with 20° pressure angle. The number of teeth for G2 is 30T, G3 is 60T and G5 is 200T. The torque requirement of the output is 2500 lb.in and the output shaft rotates in counter clock wise direction. Based on this information, answer the following questions: (i) (ii) (iii) Calculate the train value of the gearing system and the number of teeth of gear G4. Draw the free body diagram and their magnitude of gear G3, G4 and G5. Calculate the power of motor in horsepower (hp) and the torque of the motor @3000 rpm. (iv) If an idler gear is added in between gear G4 and G5, does the diameter of the gear will have the effect on the torque of the output and state the reason why. PO1 5 marks PO1 20 marks PO1 5 marks PO2 5 marks 5 Output: T2500 lb.in @300 rpm 5 3 4 Figure Q3.2 2 Input: Motor @3000 rpm 2 Figure Q3.1 shows a double-reduction spur gearset. Pinion 1 is the driver, and it receives a torque of 3 Nm and rotates at 1800 rev/min. Pinion 1 has a module of 3 mm, 14 teeth, and a pressure angle of 20⁰. The mating gear 2 on shaft abcd has 60 teeth. Gear 3, which is the driver for the second pair of gears in the train, has a module of 5 mm, 15 teeth, and a pressure angle of 20°. Mating gear 4 has 45 teeth. (i) (ii) (iii) 45T To driven machine 15T 40 4 3 Unit in mm direction of rotation 100 40 14T From driving motor Figure Q3.1 Unit in mm 2 60T Find the overall speed ratio of the gear train. Determine the power, pitch line velocity and torque of Gear 4. Draw a free body diagram and compute all the force magnitudes of all gears. (iv) Determine the radial loads applied to at bearing A and bearing B. Sketch the countershaft AB as a free body in equilibrium. PO1/2 marks PO1/6 marks PO2/10 marks PO1/12 marks A gearing system as shown in Figure Q3.2 is used to reduce the rotational speed 3000 rpm of the motor to 300 rpm at the output shaft.If diametral pitch of the gear is P = 10 in ¹ is used for all the gears (G2 to G5) with 20° pressure angle. The number of teeth for G2 is 30T, G3 is 60T and G5 is 200T. The torque requirement of the output is 2500 lb.in and the output shaft rotates in counter clock wise direction. Based on this information, answer the following questions: (i) (ii) (iii) Calculate the train value of the gearing system and the number of teeth of gear G4. Draw the free body diagram and their magnitude of gear G3, G4 and G5. Calculate the power of motor in horsepower (hp) and the torque of the motor @3000 rpm. (iv) If an idler gear is added in between gear G4 and G5, does the diameter of the gear will have the effect on the torque of the output and state the reason why. PO1 5 marks PO1 20 marks PO1 5 marks PO2 5 marks 5 Output: T2500 lb.in @300 rpm 5 3 4 Figure Q3.2 2 Input: Motor @3000 rpm 2 Figure Q3.1 shows a double-reduction spur gearset. Pinion 1 is the driver, and it receives a torque of 3 Nm and rotates at 1800 rev/min. Pinion 1 has a module of 3 mm, 14 teeth, and a pressure angle of 20⁰. The mating gear 2 on shaft abcd has 60 teeth. Gear 3, which is the driver for the second pair of gears in the train, has a module of 5 mm, 15 teeth, and a pressure angle of 20°. Mating gear 4 has 45 teeth. (i) (ii) (iii) 45T To driven machine 15T 40 4 3 Unit in mm direction of rotation 100 40 14T From driving motor Figure Q3.1 Unit in mm 2 60T Find the overall speed ratio of the gear train. Determine the power, pitch line velocity and torque of Gear 4. Draw a free body diagram and compute all the force magnitudes of all gears. (iv) Determine the radial loads applied to at bearing A and bearing B. Sketch the countershaft AB as a free body in equilibrium. PO1/2 marks PO1/6 marks PO2/10 marks PO1/12 marks