Technical Description of Sylvania 40-Watt A15 Light Bulb

Michael Bermejo

City College of New York

English 21007: Writing for Engineers

Ms. Rodwell

March 25, 2022

 

TABLE OF CONTENTS

• INTRODUCTION…………….………………………………………………….3
  1. Background
• TOP PARTS ….………………………………………………………………….4
  1. Glass Bulb
     1. Argon gas
  2. Tungsten filament
• INSIDE PARTS………………………………………………………………….5
  1. Support wires
  2. Contact wires
  3. Glass mount
• BOTTOM PARTS……………………………………………………………….6
  1. Base
  2. Screw thread Contact
  3. Electric Foot Contact
• CONCLUSION…………………………………………………………….……7

The creation of light bulbs, specifically incandescent light bulbs have changed the way society has been able to function. This creation was invented by a very famous American Inventor known as Thomas Edison in the year of 1979. He was able to create a light bulb that generate light when an electrical current passes through the metal filament wire found in the bulb, this allows for heat to form and eventually glow. Edison felt the need to come up with a small object that can produce a high amount of electrical power. The intention was for home use.  The specific light bulb being looked at is the Sylvania 40-watt clear Incandescent light bulb. Sylvania is commonly known for being a North American Lighting Company. The company was founded in 1901. This light bulb is a continuation of the innovation created by Thomas Edison which has had a major impact on the world when it comes to industrial revolution and businesses. Even now, the reason businesses can run at night is because light bulbs were invented.

The light bulb consists of 3 main parts and 6 subparts. The 3 main parts are the glass bulb, tungsten filament, and the base. Within these parts are found the subparts which are the argon gas, the glass mount, support wires, contact wires, screw thread contact, and the electrical foot contact base. These specific parts play a vital role in the overall functionality of the incandescent light bulb.

 

The outermost part of the light bulb, as ca be seen on figure 2, is the glass bulb. The glass bulb is approximately 2 inches long and 1.9 inches wide. The shape of the glass bulb is called A15. The color of Sylvania bulb is clear meaning you can see the inside of it including the metal filaments and wires when looking at it up closely. The glass around the light bulb helps prevent the oxygen from the air to reach to hot air produced by the filament. The glass from the bulb is made out soda-lime glass. Inside this Sylvania bulb, can be found the tungsten filament. The specific filament is made from metal from a rare chemical named tungsten. The filament of the Sylvania bulb is about 1   inch long and one-hundredth of an inch thick.  The electric current is passed by the metal filament called tungsten. The purpose of this tungsten filament is to consume the heat and generate it to produce light. The temperatures of this filament can reach up to 4,500 degrees Fahrenheit. The filament heat then evaporate during this process because of the heat which causes inert gas to form within the glass bulb. The light bulbs need inert gas, usually argon, to properly contain the heat and prevent the tungsten filament from breaking apart. The inert gas plays a major factor when it comes to the bulb life. By allowing the inert gas it also gives much more resistibility for longer usage.

 

Inside the bulb, the tungsten filament helps with containing the heat to produce the light. The metal filament, as can be seen in figure 3, is held up by a glass mount which is responsible for holding up many parts of the light bulb such as the wires connected to it. There are three different wires found inside the bulb. There are several inside this incandescent bulb. The first wire, known as the Contact wires, that are lead wires connecting the tungsten filament to the Electrical foot contact. The contact wires are the thicker wires that are seen on figure 3. They are also made from metal and about ¼ inch thick. The other wire are the wires that connect from the base of the bulb to the filament providing the circuit within the bulb to continue with the travel of electrons. Within these contact wires there are also wires known as support wires. These support wires are meant to support the main contact wires, they are made of molybdenum.

 

The base is composed of two subparts, the electrical foot contact and the screw threads. The electrical foot contact has a diameter of one inch and is made from a metal. The electrical foot contact is the very bottom of the bulb that also includes a minimal amount of solder that is put to hold the object and act as the base. The screw threads hold a major role as the base of the light bulb because it has a specific pattern to it that allows for the bulb to be screwed into a specific socket to be used in objects such as a lamp or in a ceiling.  The bulb is named Sylvania A15 but the name that corresponds to its base is E26. This demonstrates how the name of the bulb only corresponds to size of the bulb, whereas the base has its own name.  This specific base is used for standard household appliances. Another common name for this specific base is the spiral base. Inside the base of the bulb can be found Insulation. The purpose of adding insulation to the bottom of the bulb helps with the resistance of heat flow because the base of the bulb is connected to a power source.

 

The Sylvania A14 bulb has a variety of uses for different applications. Such application includes ceiling lights, lamps, kitchen lights, closet lights, etc. These bulbs are used for mostly home appliances since they won’t require more than around 40-60 watt. This bulb will produce approximately 450 lumens of light. Compared to other bulbs with higher wattage, this specific bulb will not require as much energy which saves users on their electric bill.

The overall revolution of light and technology has allowed for such small objects to be created and have massive impact on the everyday lives of a human. The incandescent light bulbs have become revolutionary in introducing how electricity and energy can be combined to emit light and allow for a small object to give off such significant results. The innovation of the Sylvania A15 incandescent light bulb has helped users at home decorate their spaces and helped improve productivity in the night and in dark places at home.

References

Brannen, M. (2021, July 6). Historical figures: From lighting to lighting. SunTex. Retrieved April 6, 2022, from https://suntexllc.com/historical-figures-from-lightening-to-lighting/

Dassin, J. (2021, January 15). What is the bottom of a lightbulb called? ElectroAnswers. Retrieved March 29, 2022, from https://electroanswers.com/appliance/what-is-the-bottom-of-a-lightbulb-called/

Montes de Oca, S. (2021, December 29). Home Lighting 101: A guide to understanding light bulb shapes, sizes, and codes. Super Bright LEDs Knowledgebase. Retrieved April 6, 2022, from https://www.superbrightleds.com/blog/home-lighting-101-guide-understanding-light-bulb-shapes-sizes-codes/2315/

Soffar, H. (2019, November 28). Uses of light bulbs and their structure. Science online. Retrieved March 29, 2022, from https://www.online-sciences.com/the-electricity/uses-of-light-bulbs-and-their-structure/

Edison’s lightbulb. The Franklin Institute. (2017, May 19). Retrieved March 29, 2022, from https://www.fi.edu/history-resources/edisons-lightbulb#:~:text=Edison%20was%20trying%20to%20come,lights%20suitable%20for%20home%20use.