MAGNETO IGNITION SYSTEM , ITs ADVANTAGES AND DISADVANTAGES

In this system, The battery is replaced with a magneto. This system is used in Two wheelers like motor cycles, scooters etc.

Construction :

It consists of a switch , magneto , contact breaker, condenser, distributor and spark plugs.

WORKING :

The Magneto Ignition system consists of a rotating magnetic assembly driven by a engine and a fixed armature. The armature consists of primary and secondary windings. The primary circuit consists of a primary winding condenser and contact breaker. The secondary circuit consists of a secondary windings, distributor and spark plugs.

When the contact breaker points are closed :

1. The current flows in the primary circuit.

2. This produces a magnetic field in the primary winding.

3. When the primary current is at the highest peak, the contact breaker points will be opened by the cam,

When the contact breaker points are opened :

1. There is a break in the primary circuit.

2. The magnetic field in the primary winding is suddenly collapsed.

3. A high voltage (15000 volts) is generated in the secondary winding.

4. This high voltage is distributed to the respective spark plugs through the rotor of the distributor .

5. The high voltage tries to cross the spark plug gap and a spark is produced in the gap. This spark ignites the fuel-air mixture in the engine cylinder.

ADVANTAGES :

* It has no maintenance problem like coil ignition (i.e for battery)

* When the speed increases, it provides better intensity of spark and thus provides better combustion as compared to battery coil ignition system.

* Less space is required as compared to Battery Ignition System.

* It is very light in weight and compact in size.

DISADVANTAGES :

* Initial cost is very high as compared to Coil Ignition System.

* Minimum 75 rpm is necessary to start the engine.

* For higher power engines, some other devices are necessary to start Ignition.

Comments

ELECTRICAL COMPARATORS AND ITS WORKING

Electrical Comparators are used as a means of detecting and amplifying small movements of a work contacting elements. An electrical comparator consists essentially of a pick-up head or transducer for converting a displacement into a corresponding change in current and a meter or recorder connected in the circuit to indicate the electrical change, calibrated to show in terms of displacement. Generally, an amplifier is needed to provide the requisite sensitivity and to match the characteristics of different parts of the circuit. Electrical comparators can be classified according to the electrical principle used in the pick-up head. Most of the comparators use either a differential transformer, an inductance bridge, a strain gauge or a capacitor as a means of detecting movement of the gauging element. There are different types of electrical comparators. One kind called an electrolimit gauge is used to check or measure the outside diameter of a roll. The objec...

SIMPLE CARBURETOR - CONSTRUCTION AND WORKING

CONSTRUCTION OF SIMPLE CARBURETOR : The main Components of Simple Carburetor are : Float Chamber, float, nozzle, venturi, throttle valve, inlet valve, and metering jet . In the float chamber, a constant level of petrol is maintained by the float and a needle valve. The float chamber is ventilated to atmosphere. This is used to maintain atmospheric pressure inside the chamber. The float which is normally a metallic hollow cylinder rises and closes the inlet valve as the fuel level in the float chamber increases to certain level. The mixing chamber contains venturi, nozzle and throttle valve. The venturi tube is fitted with the inlet manifold. This tube has a narrow opening called venturi. A nozzle is provided just below the centre of this venturi. The nozzle keeps the same level of petrol as that of the level in the float chamber. The mixing chamber has two butterfly valves. One is to allow air into the mixing chamber known as choke valve. The other is to al...

TOP POLLUTION RECORDED IN WORLD

CHERNOBYL NUCLEAR DISASTER (NUCLEAR POLLUTION) : In April 26,1986, the melt down of the Chernobyl nuclear reactor , in Russia, has leaked out the radioactive rays and radioactive materials. Effects : 1. In this Pollution nearly 2000 persons have been killed by the accident. 2. People suffered due to the illness such as, degeneration of the cells, severe bleeding, anemia, skin cancer. 3. Animals, Plants are also affected by nuclear radiation. MINAMATA EPIDEMIC (1953) : MARINE POLLUTION ( CASE STUDY ) Minamata is a small coastal village in Japan. The Chisso Chemical Company , which produces vinyl polymer plastics used organomercurial compound. The industry released its effluent into Minamata sea. The effluent containing mercury ions is converted into methyl mercury, which is highly toxic. The marine organisms like phytoplankton and zoo-planktons easily absorb the toxic methyl mercury compound. These organisms are consumed by small fishes and these are in ...

Mechinopedia For Mechanical Engineers

Search This Blog