FOUR BAR CHAIN AND INVERSIONS
The document discusses the four bar linkage mechanism. It consists of four rigid links connected by four pin joints, forming a quadilateral. The length of one link cannot exceed the sum of the other three links. A variety of mechanisms can be formed from slight variations to the four bar linkage, including changing link proportions or combining multiple linkages. The four bar linkage is the simplest closed loop mechanism and has one degree of freedom. Inversions of the four bar linkage include the beam engine, locomotive coupling rod, and Watt's indicator mechanism. The single slider crank chain converts rotary to reciprocating motion and vice versa using one sliding and three turning pairs. Inversions include pendulum pumps, oscillating cylinder engines, and internal
FOUR BAR CHAIN AND INVERSIONS
- 1. SUBMITTED BY: SAAHIL R. KSHATRIYA ENROLLMENT NO.: 150120119164 BATCH: 3C1 SUBMITTED TO: PROF. VIPAL
- 2. The Four Bar Chain It is the much preferred device for the mechanization and control of motion due to its simplicity and versatility. It consists of four rigid links which are connected in the form of a quadilateral by four-pin joints.
- 3. The Four Bar Chain It is impossible to have a four bar linkage if length of one of the links is greater than the sum of the other three. A variety of useful mechanisms can be formed from a four- link mechanism through slight variations, such as changing the character of the pairs, proportions of links and many complex link mechanism can be formed from combination of two or more such four link mechanism
- 4. Four Bar Linkage → Is the simplest of all closed loop linkage → Have three moving link, one fixed link and 4 pin joints → There is only one constraint onther linkage, which defines a definite motion
- 5. Inversion of four bar chain (quadric cycle chain)
- 6. Inversion of four bar chain Beam engine (crank and lever mechanism) A part of the mechanism of a beam engine (also known as crank and lever mechanism) which consists of four links, is shown in Fig. In this mechanism, when the crank rotates about the fixed centre A, the lever oscillates about a fixed centre D. The end E of the lever CDE is connected to a piston rod which reciprocates due to the rotation of the crank. In other words, the purpose of this mechanism is to convert rotary motion into reciprocating motion.
- 7. Inversion of four bar chain Coupling rod of a locomotive (Double crank mechanism). Watt’s indicator mechanism (Double lever mechanism).
- 9. Single Slider Crank Chain A single slider crank chain is a modification of the basic four bar chain. It consist of one sliding pair and three turning pairs. It is, usually, found in reciprocating steam engine mechanism. This type of mechanism converts rotary motion into reciprocating motion and vice versa.
- 10. Inversions of Single Slider Crank Chain 1.Pendulum pump or Bull engine. 2.Oscillating cylinder engine 3.Rotary internal combustion engine 4.Crank and slotted lever quick return motion mechanism. 5.Whitworth quick return motion mechanism.
- 12. Inversion of double slider mechanism Elliptical trammels Scotch yoke mechanism Oldham’s coupling