Internal-combustion engines – Charge forming device – Auxiliary air or gas used to inject fuel
Patent
1999-03-08
2000-12-26
Yuen, Henry C.
Internal-combustion engines
Charge forming device
Auxiliary air or gas used to inject fuel
12317917, 12317918, F02M 2300
Patent
active
061642681
DESCRIPTION:
BRIEF SUMMARY
This invention relates to fuel injection systems of the two fluid type for internal combustion engines. In such engines, metered quantities of fuel are delivered to a combustion chamber of the engine entrained in a gas, typically air, supplied from a pressurised gas source, typically a gas duct of a rail.
Such fuel injection systems, whilst not limited to, are particularly applicable to engines for use in automotive and outboard marine and recreational applications. In such engines, commercial and user considerations require that the engine start-up period be relatively short under a wide range of conditions. For example, an engine may be employed for operation under ambient and extreme ambient conditions and efficient engine operation is important no matter the conditions. An important part of achieving a rapid start-up period in such engines is the ready availability of compressed gas at an adequate pressure to assure effective fuel delivery as close to start-up as possible. However, for cost and other considerations, it is not convenient to provide a relatively large compressed air storage capacity, and in any event, there is also the risk of loss of pressure due to leakage, particularly when the engine has been inoperative for a certain period.
Typically, a compressor driven by the engine is provided as the means for supplying compressed gas to an engine having a fuel injection system of the type above described. For both reasons of economy and energy efficiency, it is customary to select the compressor capacity to closely match the air consumption rate of the engine. Thus, under start-up conditions, there is typically no reserve supply of air at the appropriate pressure for fuel delivery and the compressor, and thus the engine, must complete a number of cycles before air at the required pressure is available to assist in the injection of fuel.
The above factors each contribute to lengthening of the period between commencement of the start-up sequence of the engine and the availability of air at the required pressure to assist in the injection of fuel.
It is known from U.S. Pat. No. 4,936,279 assigned to the Applicant to provide a fuel injection system wherein fuel is injected through a selectively openable injector nozzle directly into the combustion chamber of the engine by way of gas from a pressurised gas system. However, when the engine is in start-up mode, gases delivered from an engine combustion chamber are allowed to pass through the injector nozzle into the gas supply system to assist in a more rapid pressurisation thereof.
However, as will be seen from FIG. 1 which relates to the prior art, the opening of the injector nozzle over several consecutive cycles without any control may lead to a cycling of pressure in the gas supply system. More specifically, the pressure in the rail of the gas supply system will cycle in accordance with the pressure present in the various combustion chambers of a multi-cylinder engine, each equipped with an injector nozzle which is opened at a set timing before top dead centre and closed at a different set timing before or after top dead centre. Thus, although pressurisation of the rail is achieved, there are phases of depressurisation thereof corresponding to periods when the injector nozzle of a cylinder is opened whilst the cylinder pressure is less than that to which the rail or other gas system has been charged during a previous charging or "pump-up" event. These periods of depressurisation cost time in terms of establishing the required pressure in the gas system as time is lost in recharging the rail to the value at which the previous charging event had taken it before any incremental rise in rail pressure can be achieved.
It is therefore the object of the present invention to provide further reductions in the period required to bring the gas supply system of a dual fluid fuel injection system up to a pressure which will enable satisfactory fuel injection thereby.
With this object in view, there is provided a method of operating an internal combustion engi
REFERENCES:
patent: 4674462 (1987-06-01), Koch et al.
patent: 4771754 (1988-09-01), Reinke
patent: 4926806 (1990-05-01), Ahern et al.
patent: 4936279 (1990-06-01), Ragg
patent: 5016598 (1991-05-01), Kushibe et al.
patent: 5215064 (1993-06-01), Monnier et al.
Patent Abstracts of Japan, M-1277, p. 23, JP 4-86374A.
Patent Abstracts of Japan, M-1269, p. 150, JP 4-72461A.
Malss Stephen Reinhard
Price Stuart Graham
Schnepple Thomas
Worth David Richard
Gimie Mahmoud M.
Orbital Engine Company (Australia) Pty Ltd.
Yuen Henry C.
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