Design And Analysis Air Compresser Using Quick Return Mechanisam

DESIGN AND ANALYSIS AIR COMPRESSER USING QUICK RETURN MECHANISAM

GUIDE NAME:

BATCH MEMBERS

V. VEERAPANDIPRABHU \ MECH

R.VANJIMUTHU I.VISHNU S.MOORTHIKUMAR V.SARAVANAKUMAR

OBJECTIVES • • • • •

To reduce the return stroke time of the compressor. Implementation of quick return mechanism in compressor. To maximize the compressor out put. To reduce the power intake. To reduce cost of machine.

ABSTRACT

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Quick-return (QR) mechanisms feature different input durations for their working and return stroke. A quick return mechanism is an apparatus to produce a reciprocating motion in which the time taken for travel in one direction is less than in the other. It is driven by a circular motions source (typically a motor of some sort) and uses a system of links and sliding joints. Quick return is a common feature of tools in which the action is performed in only one direction of the stroke, such as shapers and powered saws because it allows less time to be spent on returning the tool to its initial position.

• How ever using quick return mechanism in air compressor is a result of time reduction in return stroke.

INTRODUCTION • •

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A mechanism is a simplified model, usually in the form of a line diagram, which is used to reproduce the motion occurring in a machine. The purpose of this reproduction is to enable the nature of the machine. The purpose of this reproduction is to enable the nature of the motion to be investigated without the encumbrance of the various solid bodies which form the machine elements The various parts of the mechanism are called links or elements. Where two links are in contact and a relative motion is possible, then they are known as a pair. An arbitrary set of a links which form a closed chain that is capable of relative motion, and that can be made into a rigid structure by the addition of a single link, is known as a kinematics chain. To form a mechanism from a kinematics chain one of the links must be fixed. However as any of the links can be fixed, it follows that there are as many mechanism as there are links in the chain. The technique obtaining different mechanism by fixing the various links in turn is known as inversion. The objective of this experiment is to investigate the kinematics motion of a Crank and Slotted Lever Quick Return mechanism. The investigation is to show that it is indeed a quick return mechanism and to evaluate the increase in efficiency.

LITERATURE REVIEW • •

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The Crank and lever reciprocating mechanism has been modified and used for constructing high velocity impacting press. The Crank and lever reciprocating mechanism is a mechanism able to transform circular movement into reciprocating movement. In this project we are using Spraying Pump as an application. The objective of the project is to verify that the motion does have a quick return stroke and a slow forward stoke. Additionally the increase in efficiency of the system mechanism is also determined. It improves machining productivity.

EXISTING SYSTEM • • •

A crank is an arm attached at a right angle to a rotating shaft by which reciprocating motion is imparted to or received from the shaft. It is used to convert circular motion into reciprocating motion, or vice versa. The arm may be a bent portion of the shaft, or a separate arm or disk attached to it. Attached to the end of the crank by a pivot is a rod, usually called a connecting rod. The end of the rod attached to the crank moves in a circular motion, while the other end is usually constrained to move in a linear sliding motion.

PROPOSED SYSTEM • •

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In this mechanism, there is a input power supply of 230V AC. This is reduced to 12V DC. This is achieving with the help of reduction transformer (Adaptor) Once this power is giving to the DC motor it revolves to 40 rpm with the help of reduction gear box. Therefore, Speed is reduced to 40rpm. DC motor is connected to gear box which is directly connected to the pillow block bearing. This type of bearing is used in light duty applications. Then this bearing is connected to the wheel with proper shaft. In this mechanism, there are 2 links. 1st link is connected rod and 2nd link is slider. In 1st link, there are two holes. 1st hole is directly engaged with the wheel and 2nd hole is engaged with the slider (2nd link). Both the links are connected to each other with the help of Rivet. The connecting rod converts the rotary motion into reciprocating motion of slider which is directly connected to the piston of spraying pump. There is certain amount (around 1 liter) of water in the bottle. The purpose of this machine is to spray the water in desired direction having uniform deposition on this sub-straight. Therefore the pressure is created into the bottle. This pressurized water is then used for spraying with the help of nozzle

Definition of mechanism:

• A mechanism is a simplified model, usually in the form of a line diagram, which is used to reproduce the motion occurring in a machine. The purpose of this reproduction is to enable the nature of the machine. The purpose of this reproduction is to enable the nature of the motion to be investigated without the encumbrance of the various solid bodies which form the machine elements The various parts of the mechanism are called links or elements. • Where two links are incontact and a relative motion is possible, then they are known as a pair. An arbitrary set of a links which form a closed chain that is capable of relative motion, and that can be made into a rigid structure by the addition of a single link, is known as a kinematics chain. To form a mechanism from a kinematics chain one of the links must be fixed. However as any of the links can be fixed, it follows that there are as many mechanism as there are links in the chain. The technique obtaining different mechanism by fixing the various links in turn is known as inversion.

WORKING PRINCIPLE

• Kinematics Pairs •

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The relative motion between two links of a pair can take different form. Three types of a pairs are known as lower pairs and these are the frequently occurring ones Sliding such as occurs between a piston and a cylinder Turning such as occurs with a wheel on an axle Screw motion such as occurs between a nut and a bolt All other cases are considered to be combinations of sliding and rolling are called higher pairs. Strictly screw motion is a higher pair as it combines turning and sliding. Slider – Crank Mechanism The slider- crank mechanism is well known as the basis of a reciprocating engine. As shown in the diagram below it consists of three turning pairs and one sliding pair In the above diagram, the link 1 is fixed. If we now fix link 2, that is consider an inversion of the mechanism, we obtain the mechanism shown below. This is known as Whitworth Quick Return Mechanism.

Slider crank mechanism:

ANALYSIS PARAMETERS • • • • •

Wear analysis on piiston Power intake comparison Air out put comparison Graphical analysis Cost analysis

Advantages: 1) Reduce the return stroke time. 2) More efficiency then a normal compressor 3) High volume out put.

Disadvantages: 1) More Friction 2) High wear

Reference:

[1] International Journal of Engineering and Innovative Technology (IJEIT) Volume 2, Issue 11, May 2013. [2] Oldham-Coupling Second-Harmonic Balancer,‟‟ Journal of Mechanisms, Transmissions, and Automation in Design, Vol. 106, No. 3, pp. 28–2- 1984 [3] Dwivedi, S.N., „„Application of a Whitworth Quick Return Mechanism For High Velocity Impacting Press,‟‟ Mechanism and Machine Theory, Vol. 19, pp. 51–59, 1984. [4] Harry H Cheng (2004), “Computer-Aided Mechanism Design”, Journal of Mechanical Engineering Science, Vol. 220, March 14.