阅读说明：本技术 用于在多个喷射阀中识别有故障的喷射阀的方法 (Method for identifying a defective injection valve from a plurality of injection valves ) 是由 G.P.安东尼 K.甘迪班 于 2020-01-09 设计创作，主要内容包括：本发明公开了一种在多个喷射阀中识别有故障的喷射阀的方法。该方法包括在车辆的一定运行时间之后,由控制单元探测100多个喷射阀中的每个喷射阀内的燃料的第一压力梯度。在车辆的一定运行时间期间,控制单元探测102用于所喷射的燃料量的第二压力梯度。控制单元将第一和第二压力梯度相对于数据查询表进行比较104。数据查找表包括关于所喷射的燃料量的第一压力梯度和第二压力梯度的值。当第一压力梯度超过在数据查找表中所定义的阈值极限时,控制单元检查106第二压力梯度是否超过在针对所喷射的量而在数据查找表中所定义的阈值。(The invention discloses a method for identifying a defective injection valve among a plurality of injection valves. The method comprises detecting 100, by the control unit, a first pressure gradient of fuel in each of the plurality of injection valves after a certain operating time of the vehicle. During a certain operating time of the vehicle, the control unit detects 102 a second pressure gradient for the injected fuel quantity. The control unit compares 104 the first and second pressure gradients against a data look-up table. The data lookup table includes values for a first pressure gradient and a second pressure gradient with respect to the injected fuel quantity. When the first pressure gradient exceeds the threshold limit defined in the data look-up table, the control unit checks 106 whether the second pressure gradient exceeds the threshold value defined in the data look-up table for the injected quantity.)

1. A method for identifying a faulty injection valve among a plurality of injection valves; wherein the method comprises the following steps:

detecting (100), by the control unit, a first pressure gradient of the fuel within each of the plurality of injection valves after a certain operating time of the vehicle;

detecting (102), by the control unit, a second pressure gradient for the injected fuel quantity during a certain operating time of the vehicle;

comparing (104), by the control unit, the first and second pressure gradients with respective pressure gradients stored in a data look-up table; and

when the first pressure gradient exceeds a threshold limit defined in the data look-up table, checking (106), by the control unit, whether the second pressure gradient exceeds a threshold defined in the data look-up table for the injected quantity.

2. The method of claim 1, wherein the second pressure gradient is detected on the vehicle during an overload operating condition of the vehicle and under a load condition.

Technical Field

The present invention relates to the field of fuel injection valves.

Background

Injection valves are used in fuel injection systems in which fuel under pressure is injected into the injection valve. Failure of the injection valve occurs due to reasons such as wear and tear of the material of the injection valve. In the event of failure of one or more injection valves, the injection valves tend to leak excess fuel back into the fuel tank through the return flow path. In the case of a common rail system with a plurality of injection valves, it is necessary to detect an injection valve of the group of injection valves which has failed or is about to fail.

Patent application JP119586A, representative of the prior art, discloses an injection valve failure detection method and related apparatus. In order to detect faults quickly and accurately, the current pressure drop caused in the common fuel compensation tank during the current fuel injection is compared with a predetermined normal pressure drop, in order to determine an injection defect therefrom. In the engine, at a predetermined point of time, the solenoid is energized, and its injection valve 23 sequentially injects high-pressure fuel into the corresponding cylinder, so that injection into the cylinders with numbers 1, 4, 2, 6, 3, 5 is sequentially carried out in accordance with the energizing currents i1, i4, i2, i6, i3, i 5. In this process, a pressure drop is caused at a position corresponding to each excitation current in the common fuel compensation tank. This pressure drop is detected by the pressure sensor 13 so as to be input to the microcomputer by an electric signal. If the present pressure drop is not generated by the excitation current i1 at the time of fuel injection, the present pressure drop is compared with the normal pressure drop, and it is determined that the injection valve in the cylinder with number 1 causes an injection defect based on the excitation current i 1.

Drawings

Various modes of the invention will be disclosed in detail in the specification and illustrated in the accompanying drawings:

fig. 1 shows a method for identifying a defective injection valve from a plurality of injection valves.

Detailed Description

Fig. 1 shows a method for identifying a defective injection valve from a plurality of injection valves. The method comprises detecting 100, by the control unit, a first pressure gradient of fuel in each of the plurality of injection valves after a certain operating time of the vehicle. During a certain operating time of the vehicle, the control unit detects 102 a second pressure gradient for the injected fuel quantity. The control unit compares 104 the first and second pressure gradients against a data look-up table. The data lookup table includes values for a first pressure gradient and a second pressure gradient with respect to the injected fuel quantity. When the first pressure gradient exceeds the threshold limit defined in the data look-up table, the control unit checks 106 whether the second pressure gradient exceeds the threshold value defined in the data look-up table for the injected quantity.

The way the method works will be described in more detail. The proposed method is used to detect at least one defective injection valve among a plurality of injection valves which are present in a common rail system. The function of the injection valve is to inject high-pressure fuel into the engine cylinder. In the event of failure of one or more injection valves, the injection valves tend to leak excess fuel back into the fuel tank through the return flow path, and this additional leakage affects the pressure gradient (first pressure gradient). Also, a backflow leakage of the fuel (i.e., the amount of the fuel) through the pipe and into the fuel tank is increased, thereby affecting the stability of the fuel injection valve. The proposed method is therefore used to detect an impending or already malfunctioning injection valve within a group of fuel injection valves.

The proposed method uses the pressure gradient of the fuel in the injection valve to detect whether the injection valve is malfunctioning. When the fuel injection valve injects fuel into the engine cylinder, the pressure of the common rail system drops because the fuel injection valve, which keeps the fuel under pressure, now injects the same fuel into the cylinder. However, in the event of a failure of the fuel injection valve, the fuel injection valve allows fuel to leak back into the fuel tank further through the return flow path. The pressure gradient check takes place in the conditions after the run-in (Laufeinlassen), i.e. when the ignition is switched to "off". If an injection valve is subject to wear, the pressure in the common rail system is relieved through the return path at a rate wherein the rate of pressure drop increases, and this is used as an input to check for failure of the particular injection valve. A second pressure gradient is detected on the vehicle during an over-loaded operating condition of the vehicle (Ü berlaufbedinggng) and under load conditions.

The method comprises detecting (100), by the control unit, a first pressure gradient of the fuel in each of the plurality of injection valves after a certain operating time of the vehicle. During a certain operating time of the vehicle, the control unit detects 102 a second pressure gradient for the injected fuel quantity. The control unit compares 104 the first and second pressure gradients against a data look-up table. The data lookup table includes pressure gradients defined for different values of the injection quantity. The data lookup table also includes threshold values for the first and second pressure gradients defined for the particular injection valve. In the event that the first and second pressure gradients exceed the threshold, this indicates that the injection valve has failed or is subject to wear. It is now possible to detect, among a plurality of injection valves, an injection valve which has failed.

In the context of the present disclosure, "setting" or "designing" refers to a technical efficacy or a technical capability of a component, the term "setting" or "designing" being used to implement or perform one or more specified actions with reference to the technical efficacy or the technical capability when the one or more specified actions are to be implemented or to be performed. Further, the use of the terms "set" or "design" herein refers to a normal technical efficacy or capability of a component imparted by design or structure or composition, and does not refer to any particular or abnormal efficacy or capability beyond the scope of the normal technical efficacy or capability. Therefore, it is necessary to address this problem.

It should be understood that the embodiments discussed in the above description are merely illustrative and do not limit the scope of the invention in terms of the type of fuel injection valve used. Many such embodiments and other modifications and variations to the embodiments described in the specification are contemplated. The scope of the invention is limited only by the scope of the claims.