One-hundred-and-thirty years ago, Thomas Edison completed the first successful sustained test of the incandescent light bulb. With a few incremental improvements along the way, Edison’s basic technology has lit the world ever since. This is about to change. We are on the cusp of a semiconductor-based lighting revolution which will ultimately replace Edison’s bulbs with a far more energy-efficient lighting solution. Solid state LED lighting could eventually replace almost all of the hundreds of huge amounts of incandescent and fluorescent lights in use around the world today. In reality, as being a step along this path, President Barack Obama last June introduced new, stricter lighting standards that will support the phasing out of incandescent bulbs (which already are banned in areas of Europe).
To understand exactly how revolutionary Ultrathin Constant Voltage Waterproof Power Supply are as well as why they are still expensive, it is instructive to consider the way that they are manufactured and to compare this for the output of incandescent light bulbs. This article explores how incandescent lights are created and then contrasts that process with a description of the typical manufacturing process for LED lights.
So, let’s begin by examining how traditional incandescent bulbs are produced. You will see that this can be a classic example of a computerized industrial process refined in more than a century of expertise.
While individual incandescent light types differ in proportions and wattage, all of them possess the three basic parts: the filament, the bulb, and the base. The filament is made of tungsten. While very fragile, tungsten filaments can withstand temperatures of 4,500 degrees Fahrenheit and above. The connecting or lead-in wires are usually made of nickel-iron wire. This wire is dipped into a borax means to fix make the wire more adherent to glass. The bulb itself is made of glass and possesses a mixture of gases, usually argon and nitrogen, which boost the life of the filament. Air is pumped out from the bulb and substituted for the gases. A standardized base supports the entire assembly in place. The base is referred to as the “Edison screw base.” Aluminum can be used on the outside and glass employed to insulate the inside of the base.
Originally produced by hand, light manufacturing is currently almost entirely automated. First, the filament is manufactured utilizing a process referred to as drawing, where tungsten is combined with a binder material and pulled through a die (a shaped orifice) right into a fine wire. Next, the wire is wound around a metal bar referred to as a mandrel to be able to mold it into its proper coiled shape, and then its heated in a process known as annealing, softening the wire and makes its structure more uniform. The mandrel will be dissolved in acid.
Second, the coiled filament is linked to the lead-in wires. The lead-in wires have hooks at their ends which are either pressed within the end in the filament or, in larger bulbs, spot-welded.
Third, the glass bulbs or casings are made using a ribbon machine. After heating in a furnace, a continuous ribbon of glass moves along a conveyor belt. Precisely aligned air nozzles blow the glass through holes in the conveyor belt into molds, creating the casings. A ribbon machine moving at top speed can produce greater than 50,000 bulbs per hour. Right after the casings are blown, they may be cooled and then cut from the ribbon machine. Next, the inside of the bulb is coated with silica to remove the glare the result of a glowing, uncovered filament. The label and wattage are then stamped to the outside surface of each casing.
Fourth, the base of the bulb is also constructed using molds. It is made with indentations inside the form of a screw to ensure that it can simply match the socket of the light fixture.
Fifth, once the filament, base, and bulb are produced, these are fitted together by machines. First, the filament is mounted for the stem assembly, using its ends clamped for the two lead-in wires. Next, the environment within the bulb is evacuated, and the casing is stuffed with the argon and nitrogen mixture.
Finally, the base and also the bulb are sealed. The base slides onto the end in the glass bulb to ensure that hardly any other material is necessary to have them together. Instead, their conforming shapes permit the two pieces to get held together snugly, with the lead-in wires touching the aluminum base to make sure proper electrical contact. After testing, bulbs are positioned within their packages and shipped to consumers.
Bulbs are tested for both lamp life and strength. In order to provide quick results, selected bulbs are screwed into life test racks and lit at levels far exceeding normal. This provides an accurate way of measuring how long the bulb can last under normal conditions. Tests are performed in any way manufacturing plants as well as at some independent testing facilities. The typical life of the typical household bulb is 750 to one thousand hours, depending on wattage.
LED bulbs are made around solid-state semiconductor devices, and so the manufacturing process most closely resembles that utilized to make electronic products like PC mother boards.
An easy-emitting diode (LED) is a solid state electrical circuit that generates light through the movement of electrons in a semiconductor material. LED technology has been around since the late 1960s, but for the first forty years LEDs were primarily utilized in electronics devices to change miniature bulbs. In the last decade, advances in the technology finally boosted light output sufficient for LEDs to begin with to seriously compete with incandescent and fluorescent lights. Just like many technologies, as the cost of production falls each successive LED generation also improves in light quality, output per watt, as well as heat management.
Your computer industry is well fitted to manufacture LED lighting. This process isn’t a great deal diverse from creating a computer motherboard. The businesses making the LEDs themselves are generally not in the lighting business, or this is a minor element of their business. They are usually semiconductor houses that are happy cranking out their product, which is the reason prices on high-output LEDs has fallen so much within the last 15 years.
LED bulbs themselves are expensive partly since it takes numerous LEDs to obtain wide-area illumination rather than a narrow beam, as well as the assembly cost enhances the overall price. Additionally, assemblies composed of arrays of LEDs create more opportunities for product defects.
An LED light consists of four essential components: an LED circuit board, a heatsink, an electric power supply, and a shell. The lights begin as bare printed circuit boards (PCB) and luminance LED elements arrive from separate factories which concentrate on making those components. LED elements themselves create a little bit of heat, therefore the PCB utilized in lighting fixtures is special. As opposed to the standard non-conductive sandwich of epoxy and fiberglass, the circuit board is organized on a thin sheet of aluminum which works as a heatsink.
The aluminum PCB utilized in LED lights are coated using a non-conducting material and conductive copper trace lines to form the circuit board. Solder paste will be applied within the right places and then Surface Mount Technology (SMT) machines position the tiny LED elements, driver ICs, and other components on the board at ultra high speeds.
The round model of a regular light bulb signifies that most LED printed circuit boards are circular, so for simplicity of handling some of the smaller circular PCBs are combined into one larger rectangular PCB that automated SMT machinery can handle. Consider it such as a cupcake tray moving from one machine to another along a conveyor belt, then in the end the patient cupcakes are snapped clear of the tray.
Let’s take a look at the manufacturing steps for a typical LED light meant to replace a regular incandescent bulb with an Edison Screw. You will find that it is a completely different process from your highly automated processes utilized to manufacture our familiar incandescent bulbs. And, despite everything you might imagine, folks are still greatly a necessary part of manufacturing process, and not simply for testing and Quality Assurance either.
Once the larger sheets of LED circuit boards have passed via a solder reflow oven (a heat furnace that melts the solder paste), these are split up in to the individual small circuit boards and power wires manually soldered on.
The tiny power source housed within the body in the light bulb goes through an identical process, or may be delivered complete from another factory. In either case, the manufacturing steps are similar; first the PCB passes through SMT lines, this would go to a manual dual in-line package (DIP) assembly line in which a long row of factory workers add one component at a time. DIP refers to the two parallel rows of leads projecting from your sides in the package. DIP components include all integrated chips and chip sockets.
While LED lights burn repeatedly longer than incandescent or CFLs and require less than half the power, they want some form of passive heatsink maintain the high-power LEDs from overheating. The LED circuit board, which is manufactured out of 1.6-2mm thick aluminum, will conduct the heat from your dozen roughly LED elements for the metal heatsink frame and thus keep temperatures under control. Aluminum-backed PCBs are sometimes called “metal core printed circuit boards,” despite the fact that made of a conductive material the white coating is electrically isolating. The aluminum PCB is screwed in place in the heatsink which forms the reduced 50 % of the LED light bulb.
After this, the power connector board is fixed in position with adhesive. The tiny power supply converts 120/240V AC mains capability to a lower voltage (12V or 24V), it fits in the cavity behind the aluminum PCB.
Shell assembly contains locking the shell set up with screws. A plastic shell covers the ability supply and connects with all the metal heatsink and LED circuit board. Ventilation holes are included to permit hot air to escape. Wiring assembly for plug socket requires soldering wires to the bulb socket. Then shell is attached.
Next, the completed LED light is sent to burn-in testing and quality control. The burn-in test typically lasts for thirty minutes. The completed LED light is then powered up to determine if it is working properly and burned set for half an hour. Additionally there is a high-voltage leakage and breakdown test and power consumption and power factor test. Samples from the production run are tested for high-voltage leaks, power consumption, and power factor (efficiency).
The finished bulbs move through one final crimping step because the metal socket base is crimped in place, are bar-coded and identified with lot numbers. External safety labels are applied and also the bulb is inked with information, such as logo and model number. Finally, all that’s left is to fix on the clear plastic LED cover which is glued set up.
After having a final check to make sure all the different elements of the LED light are tight, then its packed into individual boxes, and bulbs are shipped out.
So, for those who have wondered why LED light bulbs are really expensive today, this explanation of methods they may be manufactured and just how that compares to the creation of traditional bulbs should help. However, it jrlbac reveals why the fee will fall pretty dramatically within the next several years. Just as the price of manufacturing other semiconductor-based products has fallen dramatically due to standardization, automation and other key steps across the manufacturing learning curve, exactly the same inexorable forces will drive on the costs of LED light production.