Editing Stratified charge engine (section)

== History ==
[[File:Brayton direct injecton 1887.jpg|thumb|Brayton direct injecton 1887]]
The principle of injecting fuel directly into the combustion chamber at the moment at which combustion is required to start was first invented by [[George Brayton]] in 1887, but it has been used to good effect in petrol engines for a long time. Brayton describes his invention as follows: "I have discovered that heavy oils can be mechanically converted into a finely-divided condition within a firing portion of the cylinder, or in a communicating firing chamber." Another part reads "I have for the first time, so far as my knowledge extends, regulated speed by variably controlling the direct discharge of liquid fuel into the combustion chamber or cylinder into a finely-divided condition highly favorable to immediate combustion". This was the first engine to use a lean burn system to regulate engine speed / output. In this manner the engine fired on every power stroke and speed / output was controlled solely by the quantity of fuel injected.

===Ricardo=== 
[[Harry Ricardo]] first began working with the idea of a lean burn "stratified charge" engine in the early 1900s. In the 1920s he made improvements on his earlier designs.

===Hesselman===

An early example of gasoline direct injection was the [[Hesselman engine]] invented by Swedish engineer [[Jonas Hesselman]] in 1925. Hesselman engines used the ultra lean burn principle and injected the fuel in the end of the compression stroke and then ignited it with a spark plug, it was often started on gasoline and then switched over to run on diesel or kerosene. The Texaco Controlled Combustion System (TCCS) was a multifuel system developed in the 1950s which closely resembled the Hesselman design. The TCCS was tested in UPS delivery vans and was found to have an overall increase in economy of about 35%.

===Honda===
[[Honda]]'s [[CVCC]] engine, released in the early 1970s models of [[Honda Civic|Civic]], then [[Honda Accord|Accord]] and [[Honda City|City]] later in the decade, is a form of stratified charge engine that had wide market acceptance for considerable time. The CVCC system had conventional inlet and exhaust valves and a third, supplementary, inlet valve that charged an area around the spark plug. The spark plug and CVCC inlet were isolated from the main cylinder by a perforated metal plate. At ignition a series of flame fronts shot into the very lean main charge, through the perforations, ensuring complete ignition. In the Honda City Turbo such engines produced a high [[power-to-weight ratio]] at engine speeds of 7,000 [[Revolutions per minute|rpm]] and above.

===Jaguar===
[[Jaguar Cars]] in the 1980s developed the [[Jaguar V12 engine]], H.E. (so called High Efficiency) version, which fit in the [[Jaguar XJ]]12 and [[Jaguar XJS]] models and used a stratified charge design called the 'May Fireball' in order to reduce the engine's very heavy fuel consumption..

===Vespa===
The [[Vespa]] ET2 scooter had a 50&nbsp;cc [[two-stroke engine]] in which air was admitted through the transfer port and a rich fuel mixture was injected into the cylinder near the spark plug just before ignition. The injection system was purely mechanical, using a timed pumping cylinder and a non-return valve.

<blockquote>
On its downward stroke it compresses the rich mixture to about 70 psi at which time the rising pressure raises a spring loaded poppet valve off its seat and the charge is squirted into the cylinder. There it is aimed at the spark plug area and ignited. The combustion pressure immediately shuts the spring-loaded poppet valve and from then on its (''sic'') just a "regular" stratified-charge ignition process with the flame front igniting those lean mixture areas in the cylinder.<ref>{{cite web|url=http://www.motorcycle.com/mo/mcvespa/et2.html |title=Motorcycle Online: Vespa ET2 |date=2005-07-28 |access-date=2014-05-10 |url-status=unfit |archive-url=https://web.archive.org/web/20050728003514/http://www.motorcycle.com/mo/mcvespa/et2.html |archive-date=July 28, 2005 }}</ref> 
</blockquote>

===Volkswagen===
[[Volkswagen]] currently uses stratified charge on its direct injection 1.0, 1.2, 1.4, 1.5, 1.8 and 2.0 litres TFSI ([[Turbo fuel stratified injection]]) gasoline engines, in combination with [[turbocharging]].

===Mercedes-Benz===

[[Mercedes-Benz]] has been employing stratified charge engines with its Blue DIRECT system.

<blockquote>
With the stratified-charge application, the 3.0L V-6 will continue to employ direct fuel injection, but the injectors have been redesigned to spray under higher pressure later in the intake stroke, just before compression, and the fuel is shaped to arrive in certain areas within the cylinder to optimize combustion.
This strategy makes for an air-fuel mix within the chamber that is much leaner than with a conventional homogeneous-charge system that fills the chamber more uniformly before combustion.
</blockquote>