G-Lader
Encyclopedia
Volkswagen
Volkswagen is a German automobile manufacturer and is the original and biggest-selling marque of the Volkswagen Group, which now also owns the Audi, Bentley, Bugatti, Lamborghini, SEAT, and Škoda marques and the truck manufacturer Scania.Volkswagen means "people's car" in German, where it is...
models. Its purpose is to increase the motive
Motive power
In thermodynamics, motive power is an agency, as water or steam, used to impart motion. Generally, motive power is defined as a natural agent, as water, steam, wind, electricity, etc., used to impart motion to machinery; a motor; a mover. The term may also define something, as a locomotive or a...
power
Power (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
output from the internal combustion engine
Internal combustion engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...
attainable with a given engine displacement
Engine displacement
Engine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre . It is commonly specified in cubic centimeters , litres , or cubic inches...
. Since it is not enough to simply inject more fuel
Fuel injection
Fuel injection is a system for admitting fuel into an internal combustion engine. It has become the primary fuel delivery system used in automotive petrol engines, having almost completely replaced carburetors in the late 1980s....
, as this produces too rich an air-fuel mixture, more intake air has to be added at the same time. This can be achieved with an exhaust-driven turbocharger
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
, or a crankshaft
Crankshaft
The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...
-driven positive displacement compressor
Gas compressor
A gas compressor is a mechanical device that increases the pressure of a gas by reducing its volume.Compressors are similar to pumps: both increase the pressure on a fluid and both can transport the fluid through a pipe. As gases are compressible, the compressor also reduces the volume of a gas...
. The G-Lader is in the compressor category, since it is crankshaft-driven and does not have the "lag" usually associated with turbocharged engines.
History
This type of air pump, notable for low noise and high efficiencyEnergy conversion efficiency
Energy conversion efficiency is the ratio between the useful output of an energy conversion machine and the input, in energy terms. The useful output may be electric power, mechanical work, or heat.-Overview:...
, was patented on 3 October 1905 by Léon Creux of France
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
(US Patent
United States Patent and Trademark Office
The United States Patent and Trademark Office is an agency in the United States Department of Commerce that issues patents to inventors and businesses for their inventions, and trademark registration for product and intellectual property identification.The USPTO is based in Alexandria, Virginia,...
801,182). Due to the very imprecise production methods of the period, however, it was not manufacturable for a long time, since the displacer (described below) inside the compressor comes within tenths of a millimetre of the housing wall without making contact. Only with the more advanced engineering methods of the 1980s
1980s
File:1980s decade montage.png|thumb|400px|From left, clockwise: The first Space Shuttle, Columbia, lifted off in 1981; American President Ronald Reagan and Soviet leader Mikhail Gorbachev eased tensions between the two superpowers, leading to the end of the Cold War; The Fall of the Berlin Wall in...
, did it become possible to produce the G-Lader.
Contrary to expectations, Volkswagen's designs turned out to need relatively frequent repair in normal operation, which was one of the reasons why that manufacturer eventually abandoned this technology at the time. The main cause of its relatively high failure rate
Failure rate
Failure rate is the frequency with which an engineered system or component fails, expressed for example in failures per hour. It is often denoted by the Greek letter λ and is important in reliability engineering....
was that Volkswagen misrepresented the G-Lader as maintenance-free. Depending on RPMs
Revolutions per minute
Revolutions per minute is a measure of the frequency of a rotation. It annotates the number of full rotations completed in one minute around a fixed axis...
, load, and design details, various parts wear out, with results ranging from impaired performance, to destruction of the G-Lader. Yet it is frequently possible to extend the life of the G-Lader, sometimes to several hundred thousand kilometres, by periodically overhauling it with suitable replacement parts.
Operation
The supercharger housing holds what is called the displacer plate (or just displacer), on both sides of which are spirals, with sealsSeal (mechanical)
A mechanical seal is a device which helps join systems or mechanisms together by preventing leakage , containing pressure, or excluding contamination...
between the latter and the housing. The housing itself also has spirals on both sides that mesh with those on the displacer. Driven by the crankshaft
Crankshaft
The crankshaft, sometimes casually abbreviated to crank, is the part of an engine which translates reciprocating linear piston motion into rotation...
, which is connected to the displacer shaft by a small belt, the displacer moves eccentrically with respect to the supercharger housing (like the rotor in a Wankel engine
Wankel engine
The Wankel engine is a type of internal combustion engine using an eccentric rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle takes place in a space between the inside of an oval-like epitrochoid-shaped housing and a rotor that...
) and, through this motion, forces the intake air into a smaller and smaller space, ultimately producing a maximum gauge pressure of 0.8 bars (11.6 psi) with standard delivered pulleys.
Sizes and car models
The German name G-Lader comes from the shape of the supercharger , which looks like the letter G. The displacer's spirals are either 40 millimetres (1.57 in) deep or, in the larger version, 59.5 millimetres (2.34 in) deep, i.e. close to 60 mm. This is the reason we see the engine designations G40 and G60G60
G60 refers to an inline-four cylinder automobile petrol engine, which uses a specific method of forced induction - by way of a specific type of supercharger...
in the names of Volkswagen models in which it was used:
- Volkswagen Polo Mk2Volkswagen Polo Mk2The Volkswagen Polo Mk2 is the second generation of the Volkswagen Polo supermini, it was produced from late 1981 until 1994.-Polo Mark 2:...
GT G40Volkswagen Polo G40The Volkswagen Polo Mk2 and Polo Mk2F were available as supercharged G40 models - called the Volkswagen Polo G40 .-Mk2:...
(Typ 86c - limited to 500 vehicles first series (all black) and a second of approx 1500) - Volkswagen Polo Mk2F GT G40Volkswagen Polo G40The Volkswagen Polo Mk2 and Polo Mk2F were available as supercharged G40 models - called the Volkswagen Polo G40 .-Mk2:...
(Typ 86c) - Volkswagen Golf Mk2 GTI G60 (Typ 19E)
- Volkswagen Golf Mk2 G60 Rallye (Typ 19E - limited to 5000 vehicles)
- Volkswagen Golf Mk2 G60 Limited (Typ 19E - limited to a special Volkswagen-Motorsport series of 71 vehicles)
- Volkswagen Corrado G60 (Corrado - Typ 53I)
- Volkswagen Passat (B3) G60 Syncro (Passat - Typ 35I)
See also
- G60G60G60 refers to an inline-four cylinder automobile petrol engine, which uses a specific method of forced induction - by way of a specific type of supercharger...
- for detailed information on the complete G-Lader engines, and subsequent Volkswagen GroupVolkswagen GroupVolkswagen Group is a German multinational automobile manufacturing group. , Volkswagen was ranked as the world’s third largest motor vehicle manufacturer and Europe's largest....
forced inductionForced inductionForced induction is the process of compressing air on the intake of an internal combustion engine . A forced induction engine uses a gas compressor to increase the pressure, temperature and density of the air...
developments