Technical Description

The Spark that Ignited the Flame

By: William Vasconcelos

Origins:

The engine was invented in 1872 by American George Brayton which was the first in its kind to have a liquid fueled internal combustion. The engine was improved shortly after by Nikolaus Otto in 1876, where the first four-stroke engine came to be. Engines themselves are essential parts of any vehicle as they allow for energy to be converted into mechanical and motion force. Despite an engine having such amazing capabilities, a certain component within it cannot go ignored, the spark plug. The spark plug was invented by German inventor, Robert Bosch in 1901. Although there is speculation that the spark plug had been invented prior to Bosch, Bosch was the one who was able to get the idea patented in 1902. Despite it being such a small component, the spark plug plays a pivotal role in the function of an engine because of its ability to correctly time when to ignite the fuel and air mixture in the combustion chamber of an engine.

Why the Plug?

As was previously mentioned, the spark plug was utilized to ignite the fuel and air mixture inside of a combustion chamber of an engine. However, prior to the plug, it was expressed by (Keegan, 2019, para. 2), that manufacturers would rely on alternative methods to create ignition such as a battery. Unfortunately, the use of batteries proved to be far too dangerous since it would cause fires, and also depleted the battery way too fast. This caused too much concern for how to conserve more power from the battery as well as make the system much safer, which led to the creation of the spark plug.

Types of Spark Plugs:

Spark plugs have been modified and improved since its creation. Currently, there are up to 5 different types of spark plugs which include copper, nickel, platinum, double platinum, iridium, and silver. Each type has its own advantages and disadvantages which make them suitable for the task which they are constructed for. Additionally, despite the main metal utilized, the structure and way in which the plug was constructed, there are other components that will be taken into consideration such as: heat range, shell design, wide gap designation and a few others. However, these will be discussed later on in more depth.

Copper/Nickel Spark Plugs

According to Zahl, T. (2014) , author of “Understanding the Different Types of Spark Plugs”, expresses how there are different types of spark plugs, the copper/nickel being the common/standard ones.

Single Platinum Spark Plugs

Single Platinum Spark Plug is the name given to it because the center electrode is made out of platinum. Although the cost compared to the “standard” spark plug is much higher due to platinum being a much more rare element it does have its advantages. These advantages include: double the lifespan, higher the resistance to carbon build-up and can be operated.

Double Platinum Spark Plugs

As was mentioned previously, the single platinum spark plugs are those with the center electrode made out of platinum. Similarly, a double platinum spark plug has both the center electrode and the ground made out of platinum. Its benefits are that it is much better than a single platinum spark plug in that it’s able to perform better and last longer. Another benefit of double platinum spark plugs are that they work very well with “wasted ignition” systems – a system in which 2 spark plugs are attached to one coil and will fire simultaneously. On the downside, it is much more costly as platinum is not very abundant in nature.

Iridium Spark Plugs

Iridium-tipped spark plugs compared to the standard plug offer better power, as well as more complete combustion that leads to smooth operating engines, and a longer lifespan. When it comes to cost, iridium spark plugs are the most expensive because of their “fine wire” centers which aim to conduct electrical energy more effectively.

Silver Spark Plugs

Last but not least, there is the silver spark plug which has the best thermal conductivity which helps in preventing them from getting damaged due to high temperatures. This type is usually found in older European vehicles such as cars and motorcycles.

Spark Plug Nomenclature:

Although a spark plug is such a small component, in order to perform its task, its intricate design contributes to its overall performance.

Some of the different parts of the spark plug are the: ground electrode, center electrode, threat, gasket, glass resistor, insulator, seals, ribs, and terminal nut. Each one of these parts performs a certain task that helps the plug be most efficient. The parts and their purposes are as follows:

Ground/Center Electrode: Metallic components that create a gap in which a high voltage from the center electrode jumps to the ground electrode thus creating a spark (both electrodes can be made up of different materials)

Thread: grooves on the body of the spark plug used to attach the spark plug to another surface

Gasket: A component placed between two different surfaces to allow for a tight seal to be created between them

Glass Resistor: a resistor that helps remove excess electrical voltage as it flows through the center electrode inside a spark plug

Insulator: a component used to dissipate heat and depending on its design it can help prevent flashover

Seals: A component similar to a gasket, in which it allows for a tight seal between two different components and prevents anything from passing between them

Ribs: Rib-shaped design on spark plug that depending on its length will determine how good the electrical insulation is. Not only that but, it can prevent electrical energy from leaking along the side of the spark plug.

Terminal Nut: Part responsible for conducting voltage to the center electrode and is attached to the high tension cable

Spark Plug Identification:

Despite its various parts as well as the different materials which it could be made out of, spark plugs also have specific codes which help determine other traits. These traits include: resistor, shell design, heat range, gap dimension and firing end design.

Resistor: The “R” present represents that the spark plug is a resistor type where all it does is reduce radio frequency interference (RFI).

Shell Design: refers to the design of the body, such as the threads and length of ribs

Heat Range: is referring to the amount of heat that the plug can withstand; the higher the number, the higher the amount of heat it can withstand

Gap Dimension: this is simply the distance of the gap between the center and ground electrodes

Firing End Design: this information shows the material which the ground and center electrodes are made out of

Coming as One:

The spark plug works by receiving voltage which enters through the terminal nut. From there the voltage is transferred to the center electrode. As it travels through the center electrode, the voltage jumps the gap between the center electrode and the ground electrode thus creating a spark. This spark then ignited the fuel and air mixture inside of the combustion chamber of the engine. That is the spark plugs main purpose, as well as be able to dissipate heat from the inside of the chamber.

Sources Cited:

History of Spark Plugs

http://knowhow.napaonline.com/a-history-of-spark-plugs/

Types of Plugs

https://www.carid.com/articles/types-of-spark-plugs.html

Silver Plug Image

https://www.google.com/search?q=silver+spark+plug&tbm=isch&ved=2ahUKEwiftbbHr-voAhVHdN8KHdgoCswQ2-cCegQIABAC&oq=silver+spark+plug&gs_lcp=ChJtb2JpbGUtZ3dzLXdpei1pbWcQARgAMgIIADIGCAAQBRAeMgYIABAIEB4yBAgAEBgyBAgAEBg6BggAEAcQHjoICAAQCBAHEB46BAgAEA06CAgAEA0QBRAeUOjBA1jgyANgsM0DaABwAHgAgAE3iAGeApIBATaYAQCgAQE&sclient=mobile-gws-wiz-img&ei=EnyXXp_kD8fo_QbY0ajgDA&bih=719&biw=414&client=safari&prmd=sivn&hl=en-us#imgrc=XSpXQJ7gCH-d9M

Wasted Ignition

http://crypton.co.za/Tto%20know/Ignition/wasted%20sp.html

Nomenclature Image

https://images.search.yahoo.com/search/images?p=spark+plug+parts+names+and+pictures&fr=mcafee&imgurl=https%3A%2F%2Fwww.ngk.com.au%2Fwp-content%2Fuploads%2F2016%2F11%2FSP-with-labels.png#id=5&iurl=https%3A%2F%2Fwww.ngk.com.au%2Fwp-content%2Fuploads%2F2016%2F11%2FSP-with-labels.png&action=click

Nomenclature Definitions