SE535631C2 - Procedure for the presence of air in an HC dosing system and corresponding HC dosing system - Google Patents

Abstract

SUMMARY The invention relates to a method of an HC dosing system, in which fuel is supplied to a supply device (230) by means of which fuel supplies at least one point of consumption (250), including the steps of determining the presence of air supplied to the supply device (230), and in determining occurrence, reducing an operating power of said feeding device (230) compared to ordinary operation. The invention also relates to a computer program product comprising program code (P) for a computer (200; 210) for implementing a method according to the invention. The invention also relates to an HC dosing system and a motor vehicle (100) equipped with the HC dosing system. Figure 2 for publication

Description

535 B31 more easily regulate the pressure at small or no dosage amounts, the system also consists of a return hose which is arranged from a pressure side of the system back to the container. According to this configuration, it is possible to cool the dosing unit by means of said diesel which during cooling fl pours from the container via the pump and the dosing unit back to the container. In this way an active cooling of the dosing unit is provided. The return flow from the dosing valve to the container is today substantially constant.

Under certain conditions, air can enter the DPF system upstream of the pump. This can e.g. take place at start-up of the DPF system after initial installation thereof. In this case, air is present in the suction hose. Furthermore, air can enter the suction hose when the DPF system has used all available fuel in the separate container, the container being empty of fuel. In this case, the pump sucks dry, whereby air is sucked into the pump via the suction hose.

According to another example, air can enter the suction hose in situations where there is a limited amount of fuel left in the separate container in the DPF system and said DPF system moves in such a way that ripples occur in the container. In this case, air can be sucked into the pump via the suction hose.

According to a further example, the suction hose may be incorrectly mounted to the pump, whereby an air leakage occurs on the upstream side of the pump. Also in this case, air can be sucked into the pump via the suction hose or in the event of a defective or damaged seal between the suction hose and the pump.

According to one example, the suction hose itself may be broken or defective in a manner that causes air to be sucked into the pump via the suction hose. In cases where air enters the pump on a suction side thereof, the fuel flow in the DPF system is adversely affected, thereby reducing a cooling effect of the 535 B31 dosing unit with the potential risk of overheating of temperature sensitive components of the dosing unit as a result.

Furthermore, a regeneration of the particulate filter of the DPF system can be adversely affected by the presence of air in the pump due to the supply of the fuel to the oxidation catalyst being restricted, the temperature thereby falling. In such a case, it will take longer to perform a desired regeneration. It will also be more difficult in such a case to control a temperature of the DPF system.

In the presence of air in the pump in the DPF system, a working pressure of the dosing unit is adversely affected. Furthermore, today it takes quite a long time to build up a normal working pressure of the DPF system in the presence of air in the pump.

Since the dosing unit is currently arranged at the exhaust system of the vehicle, which exhaust system during operation of the vehicle is heated depending on e.g. load on the engine, the dosing unit risks overheating. Overheating of the dosing unit may result in degradation of the same consideration functionality, which may result in a degraded performance thereof.

The dosing unit today comprises electrical components, some of which include a circuit board. Said circuit boards can e.g. be provided for controlling the dosing of diesel to the exhaust system of the vehicle. These electrical components are sensitive to high temperatures for several reasons. Excessive temperatures of the dosing unit can result in degradation of the electrical components, which can lead to costly repairs at a service workshop. Furthermore, diesel present in the dosing unit can at least partially change to solid form at too high temperatures, which can lead to clogging of the dosing unit. According to one example, said diesel in the dosing unit undergoes pyrolysis, said diesel being at least partially converted to coke. Thus, at least a part of said 535 B31 diesel can boil. It is therefore of the utmost importance that the temperature of the dosing unit of the DPF system does not exceed a critical temperature.

Thus, there is a need to improve the present DPF system to reduce or eliminate the above mentioned disadvantages.

SUMMARY OF THE INVENTION An object of the present invention is to provide a new and advantageous method for improving the performance of an HC dosing system in a DPF system.

An object of the present invention is to provide a new and advantageous method for improving the performance of a DPF system.

Another object of the invention is to provide a new and advantageous HC dosing system in a DPF system and a new and advantageous computer program for improving the performance of an HC dosing system in a DPF system.

Another object of the invention is to provide a new and advantageous DPF system and a new and advantageous computer program for improving the performance of a DPF system.

An object of the present invention is to provide a new and advantageous method for improving regeneration of a particle filter of an HC dosing system in the presence of air in said HC dosing system.

A further object of the invention is to provide an alternative method of an HC dosing system and an alternative computer program of an HC dosing system and an alternative HC dosing system. Another object of the invention is to provide a method of an HC dosing system in which a working pressure of the liquid can be built up more rapidly in the presence of air in a feeding device compared with known technology.

These objects are achieved with a method in an HC dosing system, where fuel is supplied to a feeding device by means of which fuel is supplied to at least one consumption point, according to claim 1.

According to one aspect of the invention, there is provided a method of an HC dosing system, in which fuel is supplied to a feeding device by means of which fuel is supplied to at least one point of consumption. The method includes the steps of: - determining the presence of air supplied to the feeding device, and - at determined operating power, feeding device compared to ordinary operation. By optimizing the start-up time of the HC dosing system in the presence of air supplied to the supply device, improved active regeneration of a particle filter can be achieved in certain applications. By time from the time the air of the feeding device is determined until the desired working pressure of the HC start-up time is meant that the presence of the dosing system has been achieved.

To minimize the impact of air or air bubbles on the HC dosing system, the innovative method can be used to adapt an operating effect of the feeding device to a prevailing situation. In the case where the operating power is reduced in the presence of air in the feeding device, a better efficiency can then be achieved.

The method may further comprise the step of determining said occurrence on the basis of detected operating power of a power source arranged to drive said feeding device, and / or on the basis of a detected discharge pressure of said feeding device, and / or on the basis of a determined time during which a deviating operation of the feeding device has taken place. By detecting a behavior of the feeding device, which behavior is characterized by the presence of air in the feeding device, an operating effect can be reduced in order thereby to improve or optimize the start-up time of the HC dosing system.

The method may further comprise the step of maintaining said reduced operating power until said occurrence has been reduced to a desired level. At said desired level, a working pressure of the HC dosing system can return to a desired arbitrary working pressure to enable efficient cooling of the consumption point, such as e.g. a dosing unit for fuel in a DPF system.

Said desired level may be a predetermined level, taking into account a detected operating power of a power source arranged to operate said feeding device, and / or taking into account a detected discharge pressure of said feeding device, and / or taking into account a fixed time during which a reduced operating power operation of the feeding device took place.

The HC dosing system may include or constitute a DPF system. The fuel can be diesel or another hydrocarbon-based fuel. The supply device may be a diaphragm pump. Said at least one point of consumption is a dosage unit.

The method may further comprise the step of reducing said operating power of said feeding device by at least 40% compared to ordinary operation.

An advantage of reducing said operating power of the feeding device is that a smaller amount of energy is required for operation of the feeding device at the same time as a higher efficiency of the feeding device is achieved. The method may alternatively include the step of reducing said 535 B31 operating power of said feeding device by at least 20% compared to ordinary operation.

The method may further comprise the step of increasing the reduced operating power of said feeding device in at least one step, or by means of ramping, to any suitable operating power. After said occurrence has reached a desired level when operating the feeding device with reduced power, the operating power of the feeding device can be controlled in any suitable manner.

This provides a versatile solution to the above problems.

The procedure is easy to implement in existing motor vehicles. Software in an HC dosing system, where fuel is supplied to a feeding device, by means of which fuel is supplied to at least one consumption point according to the invention can be installed in a control unit of the vehicle in the manufacture thereof. A buyer of the vehicle can thus be given the opportunity to choose the function of the procedure as an option. Alternatively, software comprising program code for performing the innovative process of an HC dosing system, where fuel is supplied to a feeder by at least one point of consumption, may be installed in a control unit of the vehicle during upgrade at which fuel is supplied to a service station. In this case, the software can be loaded into a memory in the control unit. Implementing the innovative procedure is thus cost-effective, especially since no additional sensors or components need to be installed in the vehicle. The required hardware is already present in the vehicle today. The invention thus provides a cost-effective solution to the above problems.

Software that includes program code in an HC dosing system, where fuel is supplied to a feeder, by means of which fuel is supplied to at least one point of consumption can be easily updated or replaced. Furthermore, different parts of the software comprising program code in an HC dosing system, where fuel is supplied to a feeding device by means of which fuel is supplied to at least one point of consumption, can be exchanged independently of each other. This modular configuration is advantageous from a maintenance perspective.

According to one aspect of the invention, there is provided an HC dosing system arranged to supply fuel to a feeding device, which feeding device is arranged to supply fuel to at least one point of consumption, the HC dosing system comprising: - means for determining the presence of air supplied to the feeding device, and - means to, in the event of an established occurrence, reduce an operating power of said feeding device compared with ordinary operation.

The HC dosing system may further comprise means for determining said occurrence on the basis of detected operating power of a power source arranged to operate said feeding device, and / or on the basis of a detected discharge pressure of said feeding device, and / or on the basis of a fixed time. during which a deviating operation of the feeding device took place.

The HC dosing system may further comprise means for maintaining said reduced operating power until said occurrence has been reduced to a desired level.

Said desired level may be a predetermined level, taking into account a detected operating power of a power source arranged to operate said feeding device, and / or taking into account a detected discharge pressure of said feeding device, and / or taking into account a fixed time during which a reduced operating power operation of the feeding device took place.

The HC dosing system may further comprise means for reducing said operating power of said feeding device by at least 40% compared to ordinary operation. The 535 B31 HC dosing system may further comprise means for increasing the reduced operating power of said feeding device in at least one step, or by ramping, to any suitable operating power.

The above objects are also achieved with a motor vehicle which includes the features of the HC dosing system. The motor vehicle can be a truck, bus or car.

According to one aspect of the invention, there is provided a computer program in an HC dosing system, wherein fuel is supplied to a feeder by means of which fuel is supplied to at least one point of consumption, said computer program comprising program code stored on a computer readable medium to cause an electronic control unit or a another computer connected to the electronic control unit to perform the steps according to any one of claims 1-9.

According to one aspect of the invention, there is provided a computer program product comprising a program code stored on a computer readable medium for performing the method steps of any of claims 1-9, when said computer program is run on an electronic control unit or another computer connected to the electronic control unit. .

Additional objects, advantages and novel features of the present invention will become apparent to those skilled in the art from the following details, as well as through the practice of the invention. While the invention is described below, it should be apparent that the invention is not limited to the specific details described. Those skilled in the art having access to the teachings herein will recognize additional applications, modifications, and incorporations in other fields, which are within the scope of the invention. SUMMARY DESCRIPTION OF THE DRAWINGS 535 B31 For a more complete understanding of the present invention and further objects and advantages thereof, reference is now made to the following detailed description which is to be read in conjunction with the accompanying drawings in which like reference numerals refer to like parts throughout the figures. Figure 1 schematically illustrates a vehicle, according to an embodiment of the invention; Figure 2 schematically illustrates a subsystem of the vehicle shown in Figure 1, according to an embodiment of the invention; Figure 3a schematically illustrates a flow chart of a method, according to an embodiment of the invention; Figure 3b schematically illustrates in further detail a flow chart of a method, according to an embodiment of the invention; and Figure 4 schematically illustrates a computer, according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE FIGURES Referring to Figure 1, a side view of a vehicle 100 is shown. The exemplary vehicle 100 consists of a tractor 110 with an engine 150 and a trailer 112. The vehicle may be a heavy vehicle, such as a truck or a bus. The vehicle can alternatively be a car.

It should be noted that the invention is suitable for use in any suitable HC dosing system and is not limited to DPF systems in motor vehicles. The innovative method and the innovative device according to an aspect of the invention are well suited for platforms other than an HC dosing system other than motor vehicles, such as e.g. watercraft. The watercraft can be of any kind, such as e.g. motorboats, ships, ferries or ships. 535 B31 11 The innovative method and the innovative HC dosing system according to an aspect of the invention are also well suited for e.g. systems including industrial engines and / or motorized industrial robots.

The innovative method and the innovative HC dosing system according to an aspect of the invention are also well suited for different types of power plants, such as e.g. an electric power plant comprising a diesel generator.

The innovative process and the innovative HC dosing system are well suited for an arbitrary engine system that includes an engine and an HC dosing system, such as e.g. at a locomotive or other platform.

The innovative method and device are well suited for an arbitrary system that includes a particulate generator (eg, an internal combustion engine) and an HC dosing system.

The innovative method and the innovative device are well suited for an arbitrary system which includes an arbitrary system which generates exhaust gases with particles and a filter which stores particles, which particles are burned during a regeneration of said filters, in particular during an active regeneration of said filters. filter.

It should be noted that the HC dosing system can be any HC dosing system, although it is exemplified herein as an HC dosing system in a DPF system of a vehicle. The feed device may be any feed device, and need not be a diaphragm pump as described herein.

The fuel of the HC dosing system can be any fuel, such as e.g. oil, such as e.g. lubricating oil, diesel or other hydrocarbon-based fuel, such as e.g. petrol, ethanol or methane, etc. 535 831 12 Here the term "link" refers to a communication link which may be a physical line, such as an optoelectronic communication line, or a non-physical line, such as a wireless connection, for example a radio or microwave link.

Here, the term "lead" refers to a passage for holding and transporting a fl uid, such as e.g. a fuel in the liquid form. The conduit can be a pipe of any suitable dimension. The conduit may consist of any suitable material, such as e.g. plastic, rubber or metal.

Herein, the term "fuel" refers to an agent used to actively regenerate a particulate filter in an HC dosing system. Said fuel is according to one embodiment diesel. Of course, other types of hydrocarbon-based fuels can be used. Here, diesel is mentioned as an example of a fuel, but a person skilled in the art realizes that the innovative method and the innovative device can be realized for other types of fuels, with the necessary adaptations, such as e.g. adjustments to adequate boiling temperature for selected fuels, in control algorithms for executing software code in accordance with the innovative procedure. Although the term HC dosing system is used herein to indicate a particulate filter system, the invention is not limited to the use of a diesel particulate filter. On the contrary, other types of particle filters can be used according to the invention. One skilled in the art will recognize what kind of fuel is best suited for regenerating the selected particulate filter.

Referring to Figure 2, a subsystem 299 of the vehicle 100 is shown.

The subsystem 299 is arranged in the tractor 110. The subsystem 299 may form part of an HC dosing system, such as e.g. a DPF system. The subsystem 299 according to this example consists of a container 205 which is arranged to contain a fuel. The container 205 is arranged to contain a suitable amount of fuel and is further arranged to be able to be refilled if necessary.

The container can hold e.g. 200 or 1500 liters of fuel.

A first line 271 is arranged to lead the fuel to a pump 230 from the container 205. The pump 230 may be any suitable pump. The pump 230 may be a diaphragm pump comprising at least one filter. The pump 230 is arranged to be driven by means of an electric motor. The pump 230 is arranged to pump the fuel from the container 205 via the first line 271 and via a second line 272 supply said fuel to a dosing unit 250.

The dosing unit 250 comprises an electrically controlled dosing valve, by means of which a fate of fuel added to the exhaust system can be controlled. The pump 230 is arranged to pressurize the fuel in the second line 272.

The dosing unit 250 is provided with a throttling unit, against which said pressure of the fuel is built up in the subsystem 299. This pressure is referred to herein as the working pressure of the HC dosing system.

The dosing unit 250 is arranged to supply said fuel to a 100. The dosing unit 250 is arranged to supply in a controlled manner a suitable amount of fuel to an exhaust system of the vehicle 100. According to this embodiment, the particulate filter (not shown) in the form of a DPF is arranged downstream of a position in the exhaust system (not shown) of the vehicle More specifically, the exhaust system where the fuel is supplied. The amount of fuel supplied to the exhaust system is intended to be used in a conventional manner for active regeneration of the particulate filter.

The dosing unit 250 is arranged at e.g. an exhaust pipe arranged to direct exhaust gases from the internal combustion engine 150 of the vehicle 100 to a particulate filter.

The dosing unit 250 is arranged in thermal contact with the exhaust system oxidation catalyst arranged upstream of said vehicle 100. This means that thermal energy is stored in e.g. an exhaust pipe, muffler, particle filter and a downstream SCR catalyst can then be led to the dosing unit 535 B31. The dosing unit 250 comprises an electronic control card, which is arranged to handle communication with a control unit 200.

The dosing unit 250 also includes plastic and / or rubber components, which may melt or otherwise be adversely affected at excessive temperatures.

The dosing unit 250 is sensitive to temperatures above a certain temperature value, such as e.g. 120 degrees Celsius. Since e.g. exhaust pipe, in the vehicle this temperature value there is a risk that the dosing unit 250 may overheat the muffler and the particulate filter 100 exceeds during operation of the vehicle or after operation of the vehicle unless cooling thereof is achieved.

A third conduit 273 is provided between the metering unit 250 and the container 205. The third conduit 273 is arranged to return a certain amount of fuel fed to the metering valve 250 to the container 205. This configuration advantageously provides cooling of the metering unit 250. In this way the metering unit 250 is cooled by a flow of the fuel as it is pumped through the metering unit 250 from the pump 230 to the container 205.

A first control unit 200 is arranged for communication with a pressure sensor 220 via a link 293. The pressure sensor 220 is arranged to detect a prevailing pressure of the fuel where the sensor is mounted. According to this embodiment, the pressure sensor 220 is arranged at the second line 272 to measure a working pressure of the fuel downstream of the pump 230. The pressure sensor 220 is arranged to continuously send signals to the first control unit 200 including information about a prevailing pressure of the fuel.

The first control unit 200 is arranged for communication with the pump 230 via a link 292. The first control unit 200 is arranged to control operation of the 535 B31 pump 230 in order to e.g. regulate the flows of fuel within the subsystem 299.

The first control unit 200 is arranged to control an operating power of the pump 230 by controlling the electric motor thereby.

The first control unit 200 is arranged to determine a prevailing operating power of the electric motor of the pump, which operating power may change depending on the presence of air in the pump 230. In the event that air enters the first line 271, a supply current to the pump changes on the basis thereof. . The first control unit 200 is arranged to monitor the pump 230 in order to be able to determine a behavior of air of the feeding device. Similarly, the first control unit 200 due to the presence of the device is arranged to monitor a working pressure of the fuel in order to be able to determine a behavior which depends on the presence of air in the feeding device.

The first control unit 200 is arranged for communication with the dosing unit 250 via a link 291. The first control unit 200 is arranged to control operation of the dosing unit 250 in order to e.g. regulate the supply of fuel to the exhaust system of the vehicle 100. The first control unit 200 is arranged to control the operation of the dosing unit 250 in order to e.g. regulate the re-supply of fuel to the tank 205.

According to one embodiment, the first control unit 200 is arranged to control the pump 230 in accordance with an aspect of the innovative method on the basis of the received signals comprising a prevailing pressure of the fuel at the area of the pressure sensor 220. In particular, the first control unit 200 according to an embodiment is arranged to, on the basis of the received signals comprising a prevailing pressure of the fuel at the area of the pressure sensor 220, control operation of the pump 230 with reduced power compared to ordinary operation where an presence of air is determined at the inlet. at pump 230 or in pump 230, in accordance with one aspect of the innovative process. The first control unit 200 is according to an embodiment arranged to control said pump 230 in accordance with an aspect of the innovative method on the basis of the signals received from the pump 230 comprising information on a prevailing actual operating power of the pump 230. In particular, the first control unit 200 according to an embodiment is arranged that on the basis of the received signals comprising a prevailing actual operating power of the pump 230 control operation thereof thereof with reduced power compared to ordinary operation where an presence of air is determined at the inlet of the pump 230 or in the pump 230, in accordance with one aspect of the innovative process.

A second control unit 210 is arranged for communication with the first control unit 200 via a link 290. The second control unit 210 may be detachably connected to the first control unit 200. The second control unit 210 may be a control unit external to the vehicle 100. The second control unit 210 may be arranged to perform the innovative method steps according to the invention. The second control unit 210 can be used to upload software to the first control unit 200, in particular software for performing the innovative method. The second control unit 210 may alternatively be arranged for communication with the first control unit 200 via an internal network in the vehicle. The second control unit 210 may be arranged to perform substantially similar functions as the first control unit 200, such as e.g. on the basis of the received signals comprising a prevailing pressure of the fuel at the area of the pressure sensor 220 control operation of the pump 230 with reduced power compared to ordinary operation in the presence of air at the pump 230. The innovative method can be performed by the first control unit 200 or the second control unit 210, or by both the first control unit 200 and the second control unit 210.

According to this embodiment, a compressed air source 260 is arranged to supply pressurized air to the dosing unit 250 via a line 261. The dosing unit 250 is arranged to use said supplied pressurized air to further distribute the fuel being dosed. The compressed air can also be used to at least partially drive the dosing unit to dose said fuel into the exhaust duct. The compressed air can also be used to, where applicable, blow out e.g. dosing unit 250. This can be done during operation of the motor 150, or after the motor 150 has been switched off.

According to one embodiment, the container 205 may be the vehicle's fuel tank, with parts of the vehicle's existing fuel system being used in accordance with the present invention. According to another example, the container may be a separate container, i.e. not the same container as the vehicle's fuel tank.

According to one embodiment, the dosing unit 250 is arranged directly at an exhaust duct of the HC dosing system. According to another example, the dosing unit 250 is provided with a passive nozzle presently provided through said exhaust duct for dosing said fuel directly into the exhaust duct.

According to one embodiment, said pump 230 is the same pump that normally generates fuel pressure for an injection system of the engine 150. According to another example, said pump 230 is a separate pump, i.e. not the same pump that normally generates the fuel pressure to the injection system.

According to one example, a precatalyst and / or oxidation catalyst is mounted in series with the particulate filter. In this case, said precatalyst and / or oxidation catalyst are arranged upstream of said particle filter.

Figure 3a schematically illustrates a flow chart of a process in an HC dosing system, where fuel is supplied to a feeding device by means of which fuel is supplied to at least one consumption point, according to an embodiment of the invention. The method comprises a first method step s301. The step s301 determining the supplied feeding device, and in the event of a determined occurrence, reducing an operating effect, comprises the steps of determining the presence of air 5 of said feeding device compared with ordinary operation. After step s301, the process is terminated.

Figure 3b schematically illustrates a flow chart of a process in an HC dosing system, where fuel is supplied to a feeding device by means of which fuel is supplied to at least one consumption point, according to an embodiment of the invention.

The method includes a first method step s310. The process step s310 includes the step of starting operation of the pump 230. The pump 230 is then operated as in normal operation. According to one example, the pump 230 is operated with an operating power that is substantially maximum under prevailing circumstances. After the process step s310, a subsequent process step s320 is performed.

Method step s320 includes the step of determining a value of at least one operating parameter. This operating parameter can e.g. be a prevailing operating pressure of the fuel of the HC dosing system. Another operating parameter may be an actual prevailing operating power of the pump 230. After the process step s320, a subsequent process step s330 is performed.

The method step s330 includes the step of determining on the basis of the value of the at least one parameter whether a first condition is satisfied. The first condition may be a condition characterized by the presence of air in the pump 230. The first condition may be a condition which includes the presence of air supplied to the pump 230. According to one example, it may be determined that the first condition is met if a prevailing working pressure of the fuel of the HC dosing system is changed from a value representing working pressure during ordinary operation to a value below a predetermined value. According to another example, it can be determined that the first condition is satisfied if an actual prevailing operating power of the pump 230 is changed from a value representing an operating power of the pump 230 during ordinary operation to a value below a predetermined value. If the first condition is satisfied 535 B31 19, a subsequent process step s340 is performed. If the first condition is not satisfied, the step s310 is performed again.

Method step s340 includes the step of reducing an operating power of the pump 230 compared to the operating power initiated in method step s310. After the process step s340, a subsequent process step s350 is performed.

Method step s350 includes the step of determining whether a second condition is met. The second condition may be a condition characterized by the presence of substantially no air in the pump 230. The second condition may be a condition characterized by the presence of substantially an acceptable amount of air in the pump 230. The second condition may be a condition involving substantially no air. no presence of air supplied to the pump 230. If the second condition is met, a subsequent step s360 is performed. If the second condition is not satisfied, the step s340 is performed again.

Method step s360 includes the step of operating the pump 230 with any suitable operating power. According to one embodiment, the operating power of the pump 230 can be controlled to an initial level. as indicated in step s310, in one or more discrete steps. According to one embodiment, the operating power of the pump 230 can be controlled to an initial level, as indicated in step s310, by means of ramping. According to one embodiment, the operating power of the pump 230 may be maintained at the reduced level for any suitable time, and then optionally increased to any suitable level. According to one embodiment, the operating power of the pump 230 can be controlled to a level below said reduced level, at least temporarily, and then optionally controlled to an arbitrarily suitable higher level, such as e.g. said initial level. After the procedure step s360, the procedure is terminated.

Referring to Figure 4, there is shown a diagram of an embodiment of a device 400. The controllers 200 and 210 described with reference to 535 B31 Figure 2 may in one embodiment comprise the device 400. The device 400 comprises a non-volatile memory 420, a data processing unit 410 and a read / write memory 450. The non-volatile memory 420 has a first memory portion 430 in which a computer program, such as an operating system, is stored to control the operation of the device 200. Further, the device 400 includes a bus controller, a serial communication port, I / O means, an A / D converter, a time and date input and transfer unit, an event counter and an interrupt controller (not shown). The non-volatile memory 420 also has a second memory portion 440.

A computer program P is provided which comprises routines for supplying fuel to a feeding device by means of which fuel is supplied to at least one point of consumption, determining the presence of air supplied to the feeding device, and if determined, reducing an operating power of said feeding device compared to ordinary operating the innovative method. Program P includes routines for maintaining said reduced operating power until said occurrence is reduced to a desired level.

The program P includes routines for reducing said operating power of said feeding device by at least 40% compared to ordinary operation, in accordance with the innovative method. The program P can be stored in an executable manner or in a compressed manner in a memory 460 and / or in a read / write memory 450.

When it is described that the data processing unit 410 performs a certain function, it is to be understood that the data processing unit 410 performs a certain part of the program which is stored in the memory 460, or a certain part of the program which is stored in the read / write memory 450.

The data processing device 410 may communicate with a data port 499 via a data bus 415. The non-volatile memory 420 is intended for communication with the data processing unit 410 via a data bus 412. The separate memory 460 is intended to communicate with the data processing unit 410 via a data bus 411. the data processing unit 410 via a data bus 414. To the data port 499, e.g. links 290, 292 and 293 are connected (see Figure 2).

The read / write memory 450 is arranged to communicate with When data is received on the data port 499, it is temporarily stored in the second memory part 440. When the received input data has been temporarily stored, the data processing unit 410 is prepared to perform code execution in a manner described above. According to one embodiment, signals received at the data port 499 include information about the actual operating power of the pump 230. According to one embodiment, signals received at the data port 499 include information about a prevailing operating pressure of the fuel. The received signals on the data port 499 can be used by the device 400 to determine the presence of air supplied to the pump 230, and at the determined occurrence, at least temporarily reduce an operating power of said pump compared to ordinary operation.

Parts of the methods described herein may be performed by the device 400 by means of the data processing unit 410 running the program stored in the memory 460 or the read / write memory 450. When the device 400 runs the program, the methods described herein are executed.

The foregoing description of the preferred embodiments of the present invention has been provided for the purpose of illustrating and describing the invention. It is not intended to be exhaustive or to limit the scope to the variants described. Obviously, many modifications and variations will occur to those skilled in the art. The embodiments were selected and described to best explain the principles of the invention and its practical applications, thereby enabling those skilled in the art to understand the invention for various embodiments and with the various modifications appropriate to the intended use.

Claims (22)

10 15 20 25 30 535 B31 22 PATENT REQUIREMENTS A method of an HC dosing system in a DPF system, wherein hydrocarbon-based fuel is supplied to a feeder (230) by means of which fuel is supplied to at least one point of consumption (250) from a container (205), said at least one point of consumption (250) being a dosing unit (250), characterized by the steps of: - determining the presence of air supplied upstream of the feeding device (230), and - in determining such occurrence, reducing an operating power of said feeding device (230) compared to ordinary operation. The method of claim 1, further comprising the step of: - determining said occurrence on the basis of detected operating power of a power source arranged to drive said feed device, and / or on the basis of a detected discharge pressure of said feed device (230), and / or on the basis of a fixed time during which a deviating operation of the feeding device (230) has taken place. The method of claim 1 or 2, further comprising the step of: - maintaining said reduced operating power until said occurrence is reduced to a desired level. A method according to claim 3, wherein said desired level is a predetermined level, taking into account a detected operating power of a power source arranged to drive said supply device (230), and / or taking into account a detected discharge pressure of said supply device (230), and / or taking into account a set time during which an operation with the feeding device (230) took place. reduced operating power of 10 15 20 25 30 535 B31 23 A method according to any one of the preceding claims, wherein the HC dosing system is comprised of a DPF system. A method according to any one of the preceding claims, wherein the fuel is diesel. A method according to any one of the preceding claims, wherein the feeding device (230) is a diaphragm pump. A method according to any one of the preceding claims, further comprising the step of: - reducing said operating power of said feeding device by at least 40% compared to ordinary operation. A method according to any one of the preceding claims, further comprising the step of: - increasing the reduced operating power of said feeding device (230) in at least one step, or by ramping, to any suitable operating power. HC dosing system in a DPF system arranged to supply hydrocarbon-based (230), feeding device (230) is arranged to supply fuel to at least one consumption point (250) from a container (205), said at least one consumption point (250) being a dosing unit (250), fuel for a feeding device characterized by - means (200; 210; 400) for determining the presence of air upstream of the supply device, and - means (200; 210; 400) for, when determining such occurrence, reduce an operating power of said feeding device (230) compared to ordinary operation. The HC dosing system according to claim 10, further comprising: - means (200; 210; 400) for determining said occurrence on the basis of detected operating power of a power source arranged to operate said feeding device (230), and / or on a basis of a detected discharge pressure of said feeding device (230), and / or on the basis of a fixed time during which a deviating operation of the feeding device (230) has taken place. The HC dosing system of claim 10 or 11, further comprising: - means (200; 210; 400) for maintaining said reduced operating power until said occurrence is reduced to a desired level. The HC dosing system of claim 12, wherein said desired level is a predetermined level, taking into account a detected operating power of a power source arranged to drive said feed device (230), and / or taking into account a detected discharge pressure of said feed device (230), and / or taking into account a set time during which an operation with reduced operating power of the feeding device (230) took place. wherein HC- HC dosing system according to any one of claims 10-13, the dosing system being comprised of a DPF system. An HC dosing system according to any one of claims 10-14, wherein the fuel is diesel. An HC dosing system according to any one of claims 10-15, wherein the feeding device is a diaphragm pump. The HC dosing system according to any one of claims 10-16, further comprising: - means (200; 210; 400) for reducing said operating power of said feeding device (230) by at least 40% compared to ordinary operation. The HC dosing system according to any one of claims 10 to 17, further comprising: - means (200; 210; 400) for increasing the reduced operating power of said feeding device (230) in at least one step, or by ramping, to any suitable operating power. 10 15 20 535 B31 25 A motor vehicle (100; 110) comprising an HC dosing system according to any one of claims 10-18. The motor vehicle (100; 110) according to claim 19, wherein the motor vehicle is something of a truck, bus or passenger car. A computer program (P) in an HC dosing system in a DPF system, wherein hydrocarbon-based fuel is supplied to a feed device (230) by means of which fuel is supplied to at least one consumption point (250), said at least one consumption point (250) being a dosing unit (250). ), wherein said computer program (P) comprises program code for causing an electronic control unit (200; 400) or another computer (210; 400) connected to the electronic control unit (200; 400) to perform the steps according to any one of claims 1-9 . A computer program product comprising a program code stored on a computer readable medium for performing the method steps of any of claims 1-9, when said computer program is run on an electronic control unit (200; 400) or another computer (210; 400) connected to the electronic control unit (200; 400).