Heating systems – Heat and power plants – Vehicle
Patent
1997-02-06
1998-03-31
Bennett, Henry A.
Heating systems
Heat and power plants
Vehicle
237 123A, B60H 102
Patent
active
057328803
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention pertains to a heater, especially for a vehicle driven by an internal combustion engine, with a burner, to which fuel is fed from a tank via a fuel line.
BACKGROUND OF THE INVENTION
Various variants of such heaters have been known. In most cases, they are used as auxiliary heaters for passenger cars, trucks, buses, and the like, and therefore are frequently also called, not quite correctly, "parking heaters." Other important fields of application are motor homes, trailers, boats and ships, and especially also construction equipment.
In vehicles with internal combustion engines, the heater is advantageously arranged in the area of the engine compartment, partly because a fuel line is available there for tapping, and partly because a relatively readily accessible space is available there for accommodating the individual parts of the heater.
The heater contains a combustion chamber, which is arranged in a space downstream of a burner and is surrounded by a space through which a heat carrier flows. Combustion air is fed to the burner via a combustion air blower, on the one hand, and fuel is fed to it from a tank by a fuel pump, on the other hand.
While the combustion chamber, the burner, the combustion air blower, and additional parts of the heater are arranged in a common housing, the fuel pump is usually located at a point removed from this housing, and it is connected to the tank via a fuel line or to a tapping point of the fuel line for the internal combustion engine, on the one hand, and to the burner, on the other hand.
Depending on the burner output set, the fuel pump delivers a varying amount of fuel per unit of time to the burner. Automatically controlled pressure pumps responding to pressure in the drain line (pressure-controlled pumps) are used as fuel pumps in conjunction with a pressure regulator. The general design of such pressure-controlled pumps will be explained in greater detail below.
A residual amount of fuel remains in the fuel line between the pressure-controlled pump and the burner after the heater has been switched off, especially when the vehicle is stopped. If the environment of the fuel line is warm or even hot, as it usually is in the engine compartment of a motor vehicle, the temperature of the fuel in the fuel line section increases, and the residual fuel evaporates in this section of the fuel line. Since the fuel pump is not running, and the return of expanding fuel through the fuel pump is ruled out by, e.g., a nonreturn valve, fuel is pressed into the burner because of the evaporating fuel and the excess pressure building up in the process in the section of the fuel line. This amount of fuel is also burned later at the time of the ignition of the burner. Measures must be taken to prevent this amount pressed into the burner from becoming large enough to cause a hazardous explosion at the time of a subsequent ignition process.
The evaporation of fuel in the line section between the fuel pump and the burner after the heater has been stopped leads to problems when the heater is subsequently switched on, because the fuel pump does not deliver fuel after it has been switched on, but first only air or gas/vapor from the section of the fuel line between the fuel pump and the burner. If the burner contains, e.g., a nozzle for atomizing the fuel, only a mixture of air, gas and fuel vapor will be discharged from the nozzle, and this mixture can never form a combustible mixture with the combustion air being fed in at the same time. If sufficient fuel supply with subsequent flame formation fails to take place within a certain period of time, the device is switched off by the safety switch, which is in connection with a flame failure controller.
Considerable disturbances may consequently occur in the operation of the heater due to the above-described processes, especially when the part of the fuel line that is located between the fuel pump and the burner is arranged in an area of the engine compartment of the vehicle where considerably high te
REFERENCES:
patent: 3840323 (1974-10-01), Eckerle et al.
patent: 4553697 (1985-11-01), Nothen et al.
patent: 4940041 (1990-07-01), Riedmaier et al.
Blaschke Walter
Brenner Dirk
Burner Erwin
Langen Herbert
Pfister Wolfgang
Bennett Henry A.
Boles Derek
J. Eberspacher GmbH & Co.
LandOfFree
Heater for a vehicle powered by an internal-combustion engine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heater for a vehicle powered by an internal-combustion engine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heater for a vehicle powered by an internal-combustion engine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-45089