DE102020113092A1 - Method for checking an injection system arranged in a motor vehicle - Google Patents

Abstract

The technology disclosed here relates according to the invention to a method for checking an injection system (20) arranged in a motor vehicle (10) for introducing an operating medium into a cavity, the injection system (20) being fluidly connected to a test injector (50) for introducing the operating medium into the cavity the method comprising the steps of: fluidly connecting a reference injector (60) to the injection system (20); Sending a signal for delivering a reference quantity of operating medium from the injection system (20) to the reference injector (60); Comparing the amount actually dispensed by the reference injector (60) in response to the signal with the reference amount; and determining the functionality of the injection system (20) depending on whether the reference quantity differs from the quantity actually dispensed by more or by no more than a predetermined value.

Description

The technology disclosed here relates to a method for checking an injection system arranged in a motor vehicle.

The injection point of an injection system, at which an operating medium is injected into a cavity of a motor vehicle by means of an injector, can be located in an inaccessible location or in a position of the motor vehicle that is difficult to access. This means that the installation or removal of the injector is technically very complex. In some cases, the engine or parts of the engine of the motor vehicle must be removed for this. If a dosing quantity error is detected in the injection system, i.e. the quantity that should be dispensed according to the signal is not dispensed, it is sometimes difficult to determine the exact cause. It is often unclear whether the injector itself is defective or whether the injection system, e.g. a pump or line that delivers an operating medium to the injector.

It is a preferred object of the technology disclosed here to reduce or remedy at least one disadvantage of a previously known solution or to propose an alternative solution. In particular, it is a preferred object of the technology disclosed here to show a method by means of which the functionality of an injection system can be checked in a technically simple manner. Further preferred objects can result from the advantageous effects of the technology disclosed here. The object (s) is / are achieved by the subject matter of claim 1 of the independent claims. The dependent claims represent preferred configurations.

In particular, the object is achieved by a method for checking an injection system arranged in a motor vehicle for introducing an operating medium into a cavity, the injection system being fluidly connected to a test injector for introducing the operating medium into the cavity, the method comprising the following steps: fluidly connecting a Reference injector with the injection system; Sending a signal for delivering a reference quantity of operating medium from the injection system to the reference injector; Comparing the amount actually dispensed by the reference injector in response to the signal with the reference amount; and determining the functionality of the injection system as a function of whether the reference quantity differs from the quantity actually dispensed by more or by no more than a predetermined value.

One advantage of this is that the test injector does not have to be removed in order to find the cause of the error (test injector or injection system). The injection system can be checked quickly and easily using this method. If the functionality of the injection system was checked with a positive result, it is determined that the test injector is not fully functional. As a result, the test injector only needs to be removed in rare cases and only if it has been determined that the injection system is functional. For example, pinched lines and / or faults in a pump that supplies the injector with operating fluid can be identified quickly and easily from a technical point of view.

According to one embodiment, the fluid connection between the test injector and the injection system is interrupted for the fluid connection of the reference injector to the injection system. One advantage of this is that the test injector is separated from the injection system. For example, a fluid line that was connected to the test injector can be repositioned so that the fluid line is connected to the reference injector. This saves time. It is possible for the reference injector to be connected to a connection point of the injection system provided for this purpose.

According to one embodiment, the method further comprises the following step: connecting at least one electrical connection of the test injector to the reference injector, the signal for delivering the reference quantity to the reference injector being sent via the electrical connection. The advantage here is that the signal for dispensing the operating medium and the electrical connection of the test injector are also checked. The reference injector receives the same electrical or electronic signal for dispensing the test quantity via the same electrical connection as the test injector. In this way, faults in the electrical connection or in the control device that sends the signal to the test injector or reference injector can also be easily detected in a technically simple manner.

According to one embodiment, the pressure of the operating medium in the injection system is also detected before, during and / or after the operating medium is dispensed by the reference injector. The advantage here is that a leak in the injection system can be identified in a technically particularly simple manner.

According to one embodiment, the injection system comprises a system for introducing an exhaust gas aftertreatment agent into an exhaust gas duct of the motor vehicle. One advantage of this is that an exhaust gas aftertreatment system can be checked for functionality in a technically particularly simple manner.

According to one embodiment, the electrical connection is made without an extension cable with the Reference injector connected. The advantage here is that the injection system is checked quickly and without introducing possible further sources of error in the form of an extension cable.

According to one embodiment, the amount actually dispensed by the reference injector is collected and measured. One advantage of this is that the amount actually dispensed can be recorded in a technically simple and particularly precise manner. Thus, a slight difference between the reference quantity that the reference injector is supposed to deliver to operating material and the amount of operating material actually delivered by the reference injector can be detected. As a result, smaller errors or smaller leakages and / or slight deviations in a pump output from the normal output of the injection system can also be recognized.

According to one embodiment, the injection system comprises a pump for delivering operating medium to the test injector. The advantage here is that the functionality of the pump is also checked in a technically simple manner.

According to one embodiment, the reference injector is constructed identically to the test injector. One advantage of this is that the functionality of the injection system is checked particularly precisely and in a technically simple manner.

According to one embodiment, the reference injector is fluidly connected to the operating medium at a separation point of an operating medium line, which leads from an operating medium container for storing the operating medium to the test injector. The advantage here is that the reference injector is technically particularly easy to fluidly connect to the injection system.

The test injector can remain fluidly connected to the injection system and / or the exhaust gas duct or can be fluidly separated from the injection system and / or the exhaust gas duct in order to fluidically connect the reference injector to the injection system.

A preferred operating fluid is AdBlue ^® . It is also conceivable that the technology disclosed here is used for storing other liquids (for example fuel, water or an aqueous solution) in a motor vehicle. Even if an operating medium container, operating medium pump and the like are mentioned here, the terms fuel container and fuel pump are also intended to be disclosed.

The technology disclosed here relates to an operating medium container which forms the storage volume for storing the operating medium. The operating medium container thus forms the essentially fluid-tight outer shell of the storage volume and delimits the storage volume from the installation space. In the case of plastic containers, for example, one speaks of the bubble. In the case of steel containers, the operating medium container can be formed from two metal shells, for example. The operating medium container can advantageously have a saddle shape, with a main chamber and a secondary chamber, which are connected to one another via a connecting area.

It is also conceivable that the operating medium container is an HDPE injection-molded tank, in particular using 2-shell technology.

In other words, the technology disclosed here relates to a method in which a reference injector is connected to an injection system in order to check whether, in the case of an injector installed in an injection system of a motor vehicle, the fault is in the injector or in the other elements or components. Components of the injection system.

• 1 eine schematische Ansicht eines Einspritzsystems eines Kraftfahrzeugs; und
• 2 eine schematische Ansicht des Einspritzsystems aus 1 mit einem angeschlossenen Referenzinjektor.

The technology disclosed here will now be explained with reference to the figures. Show it:

• 1 a schematic view of an injection system of a motor vehicle; and
• 2 a schematic view of the injection system from 1 with a connected reference injector.

1 shows a schematic view of an injection system 20th of a motor vehicle 10 .

The car 10 can be a car, a truck, a motorcycle, a bus, an airplane, a helicopter, a locomotive or a train or a ship.

The injection system 20th includes a resource container 30th a control device for storing an operating resource 40 for sending a signal to a test injector 50 for dispensing a quantity of operating medium into a cavity of the motor vehicle 10 . The control unit 40 is via an electrical connection 45 or a signal line with the test injector 50 tied together. The resource container 30th is via a resource line 35 with the test injector 50 fluid-connected. The test injector 50 is for injecting the operating fluid into a cavity, here an exhaust gas duct 70 or exhaust pipe formed.

The operating medium can comprise or be, for example, water or an agent for selective catalytic reduction (SCR). In particular, the operating means can comprise or be a means for exhaust gas aftertreatment.

The test injector 50 is often at one point on the motor vehicle 10 that is typically difficult to access, for example below the engine of the motor vehicle 10 installed. Thus, the test injector 50 usually not technically easy and quick to expand and examine or check under laboratory conditions.

If a dosing quantity error occurs, i.e. the quantity to be dispensed according to the signal (also known as the reference quantity) of operating material is not actually dispensed by the injector, but a quantity that deviates from this is dispensed, the check described below can be carried out. It is also conceivable that the check described below takes place at regular time intervals regardless of an error or an error message.

To check whether there is a fault in the injection system 20th or in the test injector 50 is present, becomes a reference injector 60 used. The reference injector 60 has been checked for its (complete) functionality. This means that it is ensured that the reference injector 60 in response to a signal to dispense a quantity, the quantity actually dispenses if the further elements or components of an injection system 20th , for example a pump for conveying equipment to the injector, etc., are fully functional. A failure of the reference injector 60 is therefore almost impossible.

2 shows a schematic view of the injection system 20th the end 1 with a connected reference injector 60 .

The reference injector 60 is at a provided separation point of the injection system 20th with the injection system 20th fluid-connected. This means that the injection system 20th has a connection to which the reference injector 60 such to the injection system 20th that can be connected to the injector operating fluid that comes from the operating fluid container 30th or the operating resources line 35 originates, can deliver. For example, the resource line 35 a connection to the test injector that can be easily separated, for example, manually or manually using a tool 50 on. The resource line 35 can be repositioned, so to speak.

It is also conceivable that the injection system 20th a connector for connecting the reference injector 60 having. This means that the test injector 50 with the injection system 20th remains connected to the fluid.

In addition, the electrical connection 45 or the electrical connections, eg power supply and / or signal line from the control unit 40 , also repositioned. This means that the electrical connection 45 or the electrical connections from the test injector 50 is / are unplugged and with the reference injector 60 will be connected. This ensures that the reference injector 60 receives the same electrical or electronic values or signals that the test injector receives 50 receives.

The one from the reference injector 60 on the signal from the control unit 40 The amount actually delivered is recorded. This can be done, for example, by mechanically intercepting the data from the reference injector 60 actually delivered amount can be recorded. The amount actually dispensed can then be recorded, for example how many milliliters are used by the reference injector 60 includes dispensed amount. It is also possible to record how many pump cycles a pump has to refill the operating medium line 35 needed after or during the reference injector 60 Has delivered or is delivering resources. The volume or the amount per pump cycle is known or standardized. In this way, too, the amount actually dispensed by the reference injector 60 to be determined.

The one from the reference injector 60 The amount actually delivered is compared with the reference amount or target amount that the injector responds to the signal from the control unit 40 should have given up. For example, a difference is formed between the amount actually dispensed and the reference amount.

The difference must be less than or equal to a specified value so that it is determined that the injection system 20th is functional or fully functional. This means that the difference between the amount actually dispensed and the reference amount is less than a predefined value or equal to the predefined value. This can lead to a fault in the pump (low pump output) or a fault in the operating medium line 35 (e.g. a kink or a leak), a fault in the control unit 40 (an electrical or electronic fault) or the like can be excluded. Consequently, if the difference or the difference is less than or equal to a predetermined value, it can be concluded with high reliability or probability that the test injector 50 has an error.

If the difference is equal to or greater than a predetermined value or amount, it is determined that the injection system 20th has an error. In this error the test injector 50 typically not initially removed, but rather the fault in the injection system 20th will be examined more closely and repaired if necessary. The injection system can then be checked 20th be repeated.

Thus, the test injector must 50 can only be removed when it is certain that the test injector 50 has an error. As a result, the motor or parts of the motor may also need to be in order to operate the test injector 50 to be removed only when it is certain that the test injector 50 is the cause of the dosing quantity error.

The reference injector 60 and / or the test injector 50 may comprise or be an injection nozzle.

For reasons of legibility, the expression “at least one” has been partially omitted for the sake of simplicity. If a feature of the technology disclosed here is described in the singular or indefinitely (e.g. the / an injection system 20th , the / a resource container 30th , the / a test injector 50 , the / a reference injector 60 , etc.) at the same time their majority should also be disclosed (e.g. the at least one injection system 20th , the at least one equipment container 30th , the at least one test injector 50 , the at least one reference injector 60 , Etc.).

The term “essentially” (e.g. “essentially vertical axis”) in the context of the technology disclosed here includes the exact property or the exact value (e.g. “vertical axis”) as well as deviations that are insignificant for the function of the property / value (eg "tolerable deviation from the vertical axis").

The preceding description of the present invention is for illustrative purposes only and not for the purpose of limiting the invention. Various changes and modifications are possible within the scope of the invention without departing from the scope of the invention and its equivalents.

List of reference symbols

10

Motor vehicle

20th

Injection system

30th

Equipment container

35

Resource management

40

Control unit

45

Electrical connection

50

Test injector

60

Reference injector

70

Exhaust gas routing

Claims (10)

Method for checking an injection system (20) arranged in a motor vehicle (10) for introducing an operating medium into a cavity, the injection system (20) being fluidly connected to a test injector (50) for introducing the operating agent into the cavity, the method comprising the steps of: Fluidly connecting a reference injector (60) to the injection system (20); Sending a signal for delivering a reference quantity of operating medium from the injection system (20) to the reference injector (60); Comparing the amount actually dispensed by the reference injector (60) in response to the signal with the reference amount; and Establishing the functionality of the injection system (20) as a function of whether the reference quantity differs from the quantity actually dispensed by more or by no more than a predetermined value. Procedure according to Claim 1 wherein the fluid connection between the test injector (50) and the injection system (20) is interrupted for the fluid connection of the reference injector (60) to the injection system (20). Procedure according to Claim 1 or 2 , the method further comprising the following step: connecting at least one electrical connection (45) of the test injector (50) to the reference injector (60), the signal for dispensing the reference quantity being sent to the reference injector (60) via the electrical connection (45). Method according to one of the preceding claims, wherein the pressure of the operating medium in the injection system (20) is also detected before, during and / or after the operating medium is dispensed by the reference injector (60). Method according to one of the preceding claims, wherein the injection system (20) comprises a system (20) for introducing an exhaust gas aftertreatment agent into an exhaust gas duct (70) of the motor vehicle (10). Method according to one of the Claims 3 - 5 , the electrical connection (45) being connected to the reference injector (60) without an extension cable. Method according to one of the preceding claims, wherein the amount actually dispensed by the reference injector (60) is collected and measured. Method according to one of the preceding claims, wherein the injection system (20) is a pump for conveying operating medium to the test injector (50). Method according to one of the preceding claims, wherein the reference injector (60) is constructed identically to the test injector (50). Method according to one of the preceding claims, wherein the reference injector (60) is fluidly connected to the operating medium line (35) at a separation point of an operating medium line (35), which leads from an operating medium container (30) for storing the operating medium to the test injector (50).

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