BSc in MECHANICAL ENGINEERING

Course: Machine Elements I - AMEM 316

Professor: Dr. Antonios Lontos

Prepare by:

Georgiou Georgios

Reg. Num.: 9000

Fall 2016

TABLE OF CONTENTS
Page
1.  Introduction and input data ……………………………………………..…….
2.  General calculations ……………………………………………….………..…
3.  Forces and reactions ……………………………………………………….….
4.  Calculation for the smallest safe diameter …………………………………
5.  Keys and keyways ……………………………………………………….……..
6.  Critical speed …………………………………………………………………….
7.  General assemble gearbox with all the components ………………….... / 1
2
3
4
6
9
12
U
1. INTRODUCTION AND INPUT DATA
Assignment No 1: Shaft Design

Fig. 1 illustrates the inside mechanism of a mechanical device. The pulley is on the shaft No. 2 and is rotating by the motor through shaft No. 1. The transmission shaft No. 1 stands on two bearings and the rotational speed is transfer by the belt chain. The two shafts are made of hot-rolled alloy steel with yield strength σy=400 MPa and σuts=1000 MPa. The belt transmits (a) ….…....KW of power at (b) ….….... rpm. The belt is prestressed with a ration of (c) ….…..... The two gears are spur gears with 200 pressure angle. The bearing distance for the shaft 1 is (d) L1….….... mm and for the shaft 2 is (e) L2=….….... mm. For both shaft the safety factor is (f) SF=….….....

- Data for each student: (a/a ….…....)

Find:

·  Determine the smallest safe shaft diameter for the shaft 1 and 2. Provide a free body diagram and all necessary moment and torque diagrams.

·  Calculate the dimensions of the keys and the keyways at shaft 1 and 2 for the two gears and the pulley.

·  The critical speed of rotating shaft 2.

·  Give the construction drawings of the device. Design the full 3D part and two different cross sections. (Estimate all dimensions that are not given).


Figure 1: Device with the motor, the transmission shafts and the pulleys


2. GENERAL CALCULATIONS (Shaft 1)
8. REFERENCES

[1]  Mechanical Engineering Design, Ch. R. Mischke, J. Edward Shigley, McGraw-Hill, 7th edition, 2004.

[2]  Fundamentals of Machine Elements, B. J. Hamrock, B. Jacobson, S. R. Scmid, Mcgraw-Hill, 1999

[3]  Design of Machine Elements and Machines by Jack A. Collins, George H. Staab, Henry R. Busby, John Wiley & Sons, 2002

[4]  Machine Design: An Integrated Approach by Robert L. Norton, Robert L Norton, Prentice Hall, 2nd edition, 2000

[5]  Machine Elements in Mechanical Design by Robert L. Mott, Prentice Hall, 3rd edition, 1998

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