Arrangement in - and method for starting - an internal combustio

Details Arrangement in - and method for starting - an internal combustio Arrangement in - and method for starting - an internal combustio

1996-06-05

1998-01-06

Dolinar, Andrew M.

Internal-combustion engines

Starting device

Condition responsive control of starting device

1231793, 60607, 60612, F02N 1704, F02B 3704, F02B 3711

Patent

active

057043230

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

The present invention relates to an arrangement in an internal combustion engine and a method for starting an internal combustion engine.
A large proportion of environmentally harmful discharges from internal combustion engines takes place during and immediately after the starting phase. The most important reason for this is that this operating situation often involves incomplete combustion due to disadvantageous fuel/air ratio or to the air temperature in the cylinders being too low. A particular problem occurs in heavy vehicles with diesel engines, such as trucks, in which this may often lead to discharges in the form of so called white smoke exhaust. This white smoke contains hydrocarbons and consists mainly of unburnt fuel. Since combustion is temperature dependent, the problem is particularly obvious at cold starting of vehicles.
Many vehicles today are provided with turbo charged engines. In such engines the exhaust gases drive a turbine which in its turn drives a compressor which supplies the combustion space with air. The result is a higher charging pressure in the cylinders whereby a greater fuel quantity may be injected, with a consequently higher power output. When starting the vehicle, however, there will be a certain time lag between increased exhaust gas flow and increased charging pressure, the so called "turbo lag", during which time incomplete combustion may occur.
EP 367 406 describes a solution for reducing this time lag, whereby the compressor may also be driven by an electrical machine in order to be able to increase the charging pressure as quickly as possible during acceleration of the vehicle from starting. Under this solution and other similar earlier known solutions, build up of the charging pressure begins as soon as the engine starts, which does not solve discharge problems which occur at the moment of starting and during the period before the charging pressure and air temperature build up.


SUMMARY OF THE INVENTION

The present invention has the object of supplying compressed air to a cylinder of an internal combustion engine prior to starting the engine, without involving excessively expensive or complicated constructional modifications.
This is achieved by having a compressed air device build up the desired charging pressure, and hence also cause a temperature rise, before the engine starts.
Particularly great discharge reductions are achieved in applications for cold starting of diesel engine driven vehicles where the engine is of the so called direct injection type, i.e. where the fuel is injected directly into the engine combustion chamber.
According to an advantageous embodiment, the compressor on a vehicle provided with a turbo unit is driven by an electric motor before the starting of the vehicle's engine, with the object of increasing the charging pressure.
According to another advantageous embodiment, a second electric motor driven compressor is arranged in series with the ordinary compressor driven by the exhaust gas turbine and is arranged to start before the engine.
The invention has the further object of providing a method for starting an internal combustion engine, whereby the advantages described above are achieved.
Further features and advantages of the invention are indicated by the description below of an embodiment with reference to the attached drawings .


BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic drawing of a vehicle internal combustion engine and its air intake and exhaust gas systems.
FIG. 2 shows a schematic drawing of an alternative embodiment.


DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S)

FIG. 1 shows a schematic drawing of an internal combustion engine 2 and its air inlet and exhaust gas systems.
The engine 2 is here a diesel engine belonging to a truck and incorporates an engine block 3 with a number of combustion chambers 4, preferably in the form of cylinders, four of which are here depicted. The engine 2 is provided with an electric starter motor 6 for use in a conventional manner in starting

REFERENCES:
patent: 3676999 (1972-07-01), Oldfield
patent: 4232521 (1980-11-01), Gali Mallofre
patent: 4462348 (1984-07-01), Giardini
Patent Abstracts of Japan, vol. 14, No. 355, M-1004, abstract of JP, A, 2-123242 (Isuzu Motors Ltd), 10 May 1990.

Affiliated with

Also associated with

Rating

Arrangement in - and method for starting - an internal combustio does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Arrangement in - and method for starting - an internal combustio, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Arrangement in - and method for starting - an internal combustio will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2320970