how led light bulbs are made
Thirty years ago, Thomas Edison completed his first continuous test of incandescent lamps.
Along the way, Edison\'s basic technology has made some progress, from then on to illuminate the world.
This will change.
We\'re at the cutting edge of semiconductors.
Eventually, the lighting revolution will replace Edison\'s light bulb with more energy.
Efficient lighting solutions.
Solid State LED lighting will eventually replace almost all of the hundreds of billions of incandescent lamps and fluorescent lamps used in the world today.
In fact, as a step on this road, President Obama announced new, stricter lighting standards on last June, which will support the phasing out of incandescent lamps (
Has been banned in parts of Europe).
To understand how revolutionary LED bulbs are and why they are still expensive, it is instructive to see how they are made and compare them to the manufacture of incandescent lamps.
This article explores how incandescent lamps are manufactured, and then compares this process with the typical manufacturing process of LED bulbs.
So let\'s take a look at how traditional incandescent lamps are made.
You will find that this is a classic example of an automated industrial process refined from more than a century of experience.
While different types of incandescent lamps vary in size and wattage, they all have three basic parts: filament, bulb and base.
This filament is made of tungsten.
Although the tungsten wire is very fragile, it can withstand temperatures of 4,500 degrees Fahrenheit and above.
Connection or lead-
Wires are usually made of nickeliron wire.
Dip this wire into the borax solution to make the wire more attached to the glass.
The bulb itself is made of glass and contains a mixture of gas, usually ar and n, which increases the life of the filament.
Take out the air from the bulb and replace it with gas.
The standardized base holds the entire assembly in place.
The base is called the Edison screw base \".
\"Aluminum is used on the outside and glass insulation is used on the inside of the bottom.
Bulb Manufacturing was originally made by hand and is now almost fully automated.
First of all, the filament is manufactured using a process called stretching in which tungsten is mixed with the adhesive material and passes through the mold (
Into thin lines.
Next, the wire is wrapped around a metal rod called a core rod in order to shape it into a suitable spiral shape, and then heat it in the process called annealing to soften the wire and make its structure more uniform.
Then dissolve the core rod in acid.
Second, the coiled filament is attached to the leadin wires. The lead-
There are hooks at the end of the wire, which are pressed at the end of the filament, or in larger bulbs, with spotswelded.
Third, the glass bulb or shell is produced with a ribbon machine.
After heating in the stove, a continuous glass belt moves along the conveyor belt.
The precisely aligned air nozzle blows the glass through the holes on the conveyor belt into the mold to form the housing.
The high-speed ribbon machine can produce more than 50,000 bulbs per hour.
After the shell is blown out, they are cooled and then cut off the ribbon machine.
Next, the bulb is coated with silica inside to eliminate glare from glowing, uncovered filaments.
The label and wattage are then printed on the top of the exterior of each case.
Fourth, the base of the bulb is also built with a mold.
It is made with a screw-shaped dent so that it can be easily mounted on the socket of the lamp.
Fifth, once the silk, the base and the bulb are manufactured, they are assembled together by the machine.
First, install the filament onto the stem assembly with its end fixed on both leadsin wires.
Next, evacuate the air inside the bulb and fill it in the Shell with ar and nitrogen mixture.
Finally, the base and bulb are sealed.
The base slides to the end of the glass bulb, so no other material is needed to keep them together.
Instead, they meet the required shape to allow two pieces to be tightly combined with the lead
In the wire that touches the aluminum base to ensure the correct electrical contact.
After testing, the bulb is put into the package and shipped to the consumer.
The life and strength of the bulb have been tested.
To provide quick results, twist the selected bulb into the life test rack and light it up far beyond normal levels.
This provides an accurate measurement of how long the bulb lasts under normal circumstances.
The ownership of the factory and some independent testing facilities are tested.
Depending on the wattage, the average life of a typical household bulb is 750 to 1,000 hours.
LED bulbs are built around solids
Therefore, the manufacturing process is very similar to the process of manufacturing electronic products such as PC Master boards. A light-LEDs (LED)
It is a solid state circuit that produces light through the motion of electrons in semiconductor materials.
LED technology has been around since the end of 1960, but in the first 40 years LED was primarily used in electronic devices to replace miniature bulbs.
Over the past decade, advances in this technology have ultimately improved the light output, enough to allow LEDs to start competing with incandescent and fluorescent bulbs.
As with many technologies, each generation of LED products has also improved in light quality, output per watt, and thermal management as production costs have declined.
The computer industry is perfect for making LED lighting.
This process is not much different from making a computer motherboard.
Companies that make LEDs are usually not in the lighting industry or are a small part of their business.
They tend to be semiconductor companies and they are happy to launch their products which is why the price is high
Output LEDs have dropped a lot in the past 15 years.
The LED bulb itself is expensive, in part because a lot of LED is needed to be wider --
The area lighting is not a narrow beam, and the cost of Assembly increases the overall price.
In addition, components made up of LED arrays create more opportunities for product defects.
The LED light consists of four basic components: LED circuit board, radiator, power supply and housing.
The lamp starts to go out as a bare printed circuit board (PCB)
And the high-brightness LED elements come from independent factories that specialize in these components.
The LED element itself generates some heat, so the PCB used for lighting equipment is special.
Not the standard.
The circuit board is a conductive sandwich made of epoxy resin and fiberglass, spread on an aluminum sheet as a radiator.
Aluminum PCB for LED lighting
The conductive material and conductive copper trace form the circuit board.
Then apply the solder paste in the correct position and then use the surface mounting technology (SMT)
The machine places tiny LED elements, driver ic and other components on the board at an extremely high speed.
The circular shape of the conventional bulb means that most LED printed circuit boards are circular, so for ease of handling, several smaller circular PCBs are combined into a larger rectangular PCB, automated SMT machinery can be processed.
Imagine it\'s like a cupcake tray, moving from one machine to another along the conveyor belt, and then at the end, a single cupcake snapped up from the tray for free.
Let\'s take a look at the manufacturing steps of a typical LED bulb designed to replace standard incandescent lamps with Edison screws.
You will see that this is a very different process from the highly automated process of manufacturing incandescent lamps that we are familiar.
As you can imagine, people are still a very necessary part of the manufacturing process, not just for testing and quality assurance.
Once the larger LED circuit board is welded through the reflow furnace (
Hot blast stove with melted solder paste)
They are manually welded to individual small circuit boards and power cords.
The small power supply installed in the bulb body goes through a similar process or can be fully delivered from another factory.
In both cases, the manufacturing steps are the same;
First, the PCB goes through the SMT line and then into the manual dual inputline package (DIP)
Assembly line, a long row of factory workers add a component at a time.
DIP refers to two rows of parallel leads protruding from the side of the package.
DIP components include all integrated chips and chip sockets.
While LED lights burn several times longer than incandescent or CFLs and require less than half the energy they need, they need some form of passive radiator to stay high
Overheating power indicator.
LED circuit board made of 1. 6-
The 2mm thick aluminum will conduct the heat of more than a dozen LED elements onto the metal radiator frame, thus keeping the temperature constant. Aluminum-
Backing pcb is sometimes called \"metal core printed circuit board\" and although the white coating is made of conductive material, it is electrically isolated.
The aluminum PCB is screwed inside the radiator to form the lower half of the LED bulb.
After that, fix the power connector board in place with adhesive.
The small power supply converts the 120/240 v ac power supply to a lower voltage (12V or 24V)
, It is installed in the cavity behind the aluminum PCB.
The housing assembly includes locking the housing in place with screws.
The power supply is covered by a plastic housing and is connected to a metal radiator and LED circuit board.
Ventilation holes are included to allow hot air to escape.
The wiring assembly of the plug socket needs to weld the wire to the bulb socket.
Then connect the shell.
Next, send the completed LED light to burn-
In terms of testing and quality control. The burn-
The test usually lasts 30 minutes.
The completed LED bulb is then powered on to see if it works and burns within 30 minutes.
And a high-
Voltage leakage and breakdown tests as well as power consumption and power factor tests.
High samples in production operation
Voltage leakage, power consumption and power factor (efficiency).
When the base of the metal socket is curled in place, the finished bulb goes through the last curl step, which is bar-
Code and identify with batch number.
The application of external security labels, light bulbs are connected with information such as brands and models.
Finally, the rest is fixed on the transparent plastic LED cover that is glued in place.
After a final check, make sure all the different parts of the LED light are tight, then wrap it in a separate box and the light bulb will be shipped out.
So if you want to know why LED bulbs are so expensive today, this explanation of how they are made and compared to traditional bulb manufacturing should help.
However, it also reveals why costs will fall sharply in the coming years.
Like the cost of making other semiconductors.
Due to other key steps on the standardized, automated and manufacturing learning curve, product-based prices have fallen sharply, and the same unstoppable force will reduce the cost of LED bulb production.