straight line motion mechanism

abhishek joshi
mechanical engineer

1. STRAIGHT LINE MOTION MECHANISM Submitted to: Mr. N.S.GAIRA DEPARTMENT OF MECHANICAL ENGINEERING SUBMITTED BY: ABHISHEK JOSHI ROLL NO - 07 B.TECH (M.E) IV SEM

2. CONTENT WHAT IS MECHANISM ? STRAIGHT LINE MOTION MECHANISM PAUCELLIER MECHANISM APPLICATIONS OF PAUCELLIER MECHANISM ROBERT MECHANISM APPLICATIONS OF ROBERT MECHANISM

3. WHAT IS MECHANISM ? Number of rigid bodies arranged in such a way that motion of one body causes constrained and predictable motion to the other. Transmits and modifies motion.

4. STRAIGHT LINE MOTION MECHANISM Converts rotary motion into a straight line motion. Developed by J ames Watt for reciprocating piston of steam engine. Classified in two types: 1- Exact straight line mechanisms:- Paucellier mechanism, Hart mechanism, Scott- Russel mechanism, Kempe mechanism,etc . 2- Approximate straight line mechanisms:- Modified Scott- Russel mechanism, Grasshopper mechanism, Watt mechanism, Robert mechanism, etc.

5. STRAIGHT LINE MECHANISMS

6. PAUCELLIER MECHANISM Invented in 1864. Also knows as Paucellier-Lipkin linkage. First true planar straight line mechanism. Named after a French army officer Charles-Nicolas Peaucellier and a Lithuaninan mathematician Yom Tov Lipman Lipkin . Exact straight line motion mechanism.

7. GEOMETRY 6 bars of fixed lengths. OA=OC AB=BC=CD=DA, forming a rhombus. O is fixed. B moves around O. Straight line motion obtained from point D.

8. WORKING

9. PHYSICAL APPLICATION

10. ROBERTS MECHANISM Converts rotary motion to approximate straight line motion. Developed by Richard Roberts. Four bar linkage. AC=BD CD || AB (fixed link) ABCD forms trapezium. P traces an approximate straight line motion.

11. WORKING

12. APPLICATION

13. THANK YOU