Internal-combustion engines – Cooling – Automatic coolant flow control
Reexamination Certificate
2000-12-22
2002-10-29
Hirsch, Paul J. (Department: 3747)
Internal-combustion engines
Cooling
Automatic coolant flow control
C123S041440
Reexamination Certificate
active
06470838
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to a device for regulating the cooling of a motor-vehicle internal-combustion engine.
BACKGROUND OF THE INVENTION
In present-day internal-combustion-engined motor vehicles, the cooling device comprises a cooling circuit traveled by a fluid, which is generally water with antifreeze added. This circuit comprises a cooling branch containing a cooling radiator associated with a motor-driven fan unit, as well as a heating branch containing an air heater. The cooling radiator is swept by a flow of outside air which is put into motion by the speed of the vehicle and/or by the motor-driven fan unit. The cooling branch may also include a controlled valve.
The heating branch contains an air heater, that is to say a heating radiator which is traversed by an airflow put into motion by a blower. This airflow is then sent into the passenger compartment and distributed via appropriate distribution vents. The air heater forms part of a heating and/or air-conditioning installation with adjustable air-heating parameters.
The fluid pump (also called water pump) is usually driven mechanically by the engine, such that the throughput of the pump depends directly on the speed of the engine. It results therefrom that the energy taken up by the pump from the engine shaft is often very much higher than is strictly necessary. Moreover, it very often happens that the throughput of fluid in the air heater, which up to the present has been proportional to the speed of the engine, is insufficient to provide good heat-exchange effectiveness, and thus is insufficient to provide heating for the passenger compartment, especially when the engine is running at idling speed.
The object of the invention is especially to surmount the abovementioned drawbacks.
In particular the invention envisages the regulation of the cooling of the internal-combustion engine in a start-up state with the engine hot, which may also be called re-starting state.
SUMMARY OF THE INVENTION
According to the present invention there is provided a device for regulating the cooling of a motor-vehicle internal-combustion engine, of the type comprising a cooling circuit traveled by a fluid under the action of a pump, this circuit comprising a cooling branch containing a cooling radiator associated with a motor-driven fan unit, as well as a heating branch containing an air heater, wherein the pump and the motor-driven fan unit are each actuated by a variable-speed electric motor, and which comprises:
first means for establishing a hot-starting state of the engine as a function of chosen conditions; and
second means, active in this hot-starting state, for controlling the speed of the pump and the speed of the motor-driven fan unit under chosen conditions, taking account of at least one predetermined law, as a function of a first magnitude representative of the temperature of the fluid and of a second magnitude representative of the heating demand.
Thus, the device of the invention first of all determines whether the engine is in a hot-starting state and, if so, it controls the speed of the pump and the speed of the motor-driven fan unit under chosen conditions, that is to say as a function of at least one predetermined law.
In particular, the device calculates the speed of the pump (and thus its throughput) and the speed of the motor-driven fan unit, so as to ensure optimum regulation over the duration of this hot-starting state.
The means for establishing the hot-starting state of the engine advantageously comprise means for detecting that the engine is running, at zero speed of the vehicle, and means for measuring or estimating a temperature representative of the thermal state of the engine and for comparing it with at least one given threshold.
This temperature representative of the thermal state of the engine is advantageously the temperature of the fluid leaving the engine.
In one preferred embodiment of the invention, the second means are able to:
either drive the motor-driven fan unit at a minimum speed if the temperature of the fluid is above a first threshold;
otherwise, stop the motor-driven fan unit if the temperature of the fluid is below this first threshold and above a second threshold.
In this preferred embodiment, the second means are moreover able to:
either drive the pump at a minimum speed if the heating demand is zero;
otherwise, drive the pump as a function of a saturation speed, if the heating demand is positive.
The invention advantageously provides for the cooling branch moreover to comprise a controlled valve. In this case, it is advantageous for the second means to be able, moreover, to regulate this controlled valve as a function of the temperature of the fluid.
More particularly, provision is advantageously made for these second means to be able to:
either set the controlled valve to an intermediate position supplying a given temperature difference of the fluid between the inlet and outlet of the engine, when the temperature of the fluid is above a first threshold;
otherwise, close the controlled valve if the temperature of the fluid is below this first threshold and above a second threshold.
Advantageously, the intermediate position of the controlled valve corresponds to a maximum temperature difference, which may be of about 10° C.
The first temperature threshold and the second threshold which are defined above may, by way of example, be about 110° C. and about 50° C. respectively.
REFERENCES:
patent: 5018484 (1991-05-01), Naitoh
patent: 5165371 (1992-11-01), Hosseini
patent: 5529028 (1996-06-01), Weikert
patent: 5619957 (1997-04-01), Michels
patent: 6016774 (2000-01-01), Bokkers et al.
patent: 6109219 (2000-08-01), Sano
patent: 6178928 (2001-01-01), Corrineau
patent: 6213061 (2001-04-01), Bartolazzi et al.
patent: 6227183 (2001-05-01), Till
patent: 0442489 (1991-08-01), None
patent: 0965737 (1999-12-01), None
Ap Ngy Srun
Chanfreau Mathieu
Maire Arnaud
Hirsch Paul J.
Liniak Berenato Longacre & White
Valeo Thermique Moteur
LandOfFree
Device for regulating the cooling of a motor-vehicle... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for regulating the cooling of a motor-vehicle..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for regulating the cooling of a motor-vehicle... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2998687