Lighter

Lighter we use everyday many times to ignite the gas burner. But we never taught how it's working,  lets us know today.

Working mechanism

The gas lighter consists of a piezo-electric crystal over which a spring loaded hammer is placed. The hammer and spring set up is attached to button. when button is pressed , the hammer is moved away from the piezo-electric crystal. The spring releases the hammer which hits a crystal of PZT ( Piezoelectric ceramic material ) or Quartz crystal.  

Quartz is piezoelectric,which means it creates a high voltage . due to high voltage air is ionized and acts as a path for the discharge resulting a spark, which when exposed to gas and air mix it produces flame. 

Lighter

what is piezoelectric effect

piezoelectric effect is the ability of some piezoelectric material to generate an electrical charge in feedback to the mechanical stress.

piezoelectric effect is reversible ,which means when we apply mechanical stress to the piezoelectric material we receive some electrical charge on output, and when we apply electricity to the piezoelectric material , then it compress the piezoelectric material.

Piezoelectric application 

Many application we can see using piezoelectric effect like,

• Musical greeting card.
• We can generate electricity by using piezoelectric device placing on stairs,  as humans walks mechanical energy is converted into electrical energy. The energy generated here can be used for charging 40mAh button cell battery for 1 hour .

Piezoelectric effect has many uses in our day-to-day life, like when we workout in gym mechanical energy which is release can be used to convert into electricity .

medical application it's used in ultrasonic Imaging.

Induction stove

Induction stove is generally found in everyone house nowadays, if gas is empty or to cook something immediately we make use of Induction stove.

Induction cooking uses electric current directly to heat vessels through magnetic induction.

 An induction cooker transfers electrical energy by induction from a coil of wire into a metal vessel that must be ferromagnetic.

The coil is mounted under the cooking surface, and a high frequency alternating current is passed through it. The current in the coil creates a dynamic magnetic field.

Interesting facts about Induction stove.

cooking with induction stove save time, A traditional gas stove passes heat to the pan via flames, but an induction cook-top directly passes the heat to the pan.

Induction cooking saves tons of energy, instead of losing heat through flames.

Induction stove mechanism.

Inside each cooking zone, there a tightly wound coil of metal. when you turn on the power, an alternating current flows through the coil and produces an invisible high frequency, alternating magnetic field all around it. 

Place a pan on the cooking zone and the magnetic field produced by the coil penetrates the iron inside it.

The magnetic field induces electrical(eddy) current inside the pan, turning into a heater

Heat from the pan flows directly into the food or water inside it.

Induction stove 

Induction stove consists of

Induction is connected to motherboard

motherboard consists of Filter capacitors and IGBT and Rectifier Diode,

A large copper coil forms the magnetic field.

220v is passed through this device.

Voltage is 230 V and 50 Hz , power :1900 W

 

Microwave oven

Microwave oven is a part of modern kitchen today, it helps to save energy and save time.Beautiful invention has beautiful electronics in it, lets know it 

Microwaves are produced inside the oven by an electron tube called a magnetron. The microwaves are reflected within the metal interior of the oven where they are absorbed by food. Microwaves cause water molecules in food to vibrate, producing heat that cooks the food.

Few interesting facts about microwave 

Microwave oven was found during world war 2 by accident.

microwave energy was used for radar system. Accidentally scientist discovered that microwaves could be used for cooking.while conducting experiments with a new style magnetron, a candy bar in his pocket melted.

The first commercial microwave oven was produced in 1947.The oven was about 6 feet tall and weighed about 750 lbs.

The heart of  the microwave is magnetron, a device which produces radio waves. These waves excite water molecules within food ,causing them to vibrate rapidly. This vibration results in heat, cooking the food from within.

Microwave cooking times are shorter, cooking with a microwave preserve Vitamin C and other nutrients that break down when heated.

Microwave saves energy and saves time.

Microwave Heating principle.

Microwave heating is a multi-physics phenomenon that involves electromagnetic waves and heat transfer ,any material that is exposed to electromagnetic radiation will be heated up.The rapidly varying electric and magnetic fields lead to heating.

Microwave working.

Inside the strong metal box , there is a microwave generator called a magnetron. when we start cooking, the magnetron takes electricity from the power outlet and converts it into high powered  radio waves. Radio waves reaches food compartment through a channel called wave guide.just like light bounces back through wall , microwaves bounces back through wall and penetrate through food and helps in cooking.

MICROWAVE OVEN

A microwave oven consists of 

Transformer to transfer energy to the magnetron

Cavity magnetron which converts high voltage electric energy to microwave radiation

a magnetron control circuit(usually with a microcontroller)

a short wave-guide(to send waves to chamber)

metal cooking chamber

metal wave guide stiring fan

control panel.

READINGS

Commercial frequency used for microwave is 2.45 GHz.

Mixer grinder

Mixer is basic need of everyone house,without mixer cooking is impossible today ,It has special attachment to home maker. Without mixer we can't even think of cooking simple dishes.

History of mixer is very interesting 

Hebert Johnson first discovered standing mixer to help in egg mixing and dough mixing.

Mr Mathur designed Indian Mixie which helps in blending Indian Masala. It all started with  dough mixer and scientists taught its difficult to blend Indian Masala in that mixer, so the innovation of mixer came into picture. Scientists love for his wife made him to think mixer grinder to help all home maker. Braun mixer his wife was using and he was asked to repair it, however it was not suitable for Indian masala so he discovered  Indian mixer.

 Mechanism of mixer 

Mixer has universal DC motor,

Which works both in AC and DC current,mixer should run in higher RPM so that it can blend the masala nicely,

universal motor has higher power output with smaller size and starting torque to high and lower speed and to carry high load,means small device running at higher RPM to blend Indian masala.

Small device running at higher RPM  is more interesting here.

750 watt mixer

750 Watt means

Higher Wattage means running at high-speed which helps in blending the Masala neatly.For one minute how fast the blade in the Jar rotate is important.

If we run mixer by 1 hour.

power consumed is calculated by (750watt*1hr)

Energy Transformation in mixer grinder.

The rotation and electricity produces heat energy,this will make blades to rotate and produce noise and small light ,light indicates mixer is connected to electricity switch.

electrical energy is converted into mechanical,heat,noise,light energy.

400 watt mixer

400 watt mixer

Less Watt means

mixer runs at lower RPM,

1 unit of electricity means 1 kw if device is using 400 Watt total power 
total power consumed is 400/1000=0.4 KW

400 KW ,230V

Future :

Universal motor is 70% efficient.

so BL DC motor will be used for more efficient.permanent magnet outside will designed for more efficiency.