JP6164883B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine that controls an internal combustion engine including a fuel tank provided with a fuel gauge for measuring the remaining amount of fuel.

  Conventionally, in vehicles equipped with an internal combustion engine, it has been widely practiced to provide fuel detection means for detecting the remaining amount of fuel. As such a fuel detection means, for example, a float that is provided in a fuel tank and whose vertical position changes following a change in the fuel level, an arm that is connected to the float, and an arm that supports the arm are supported. A fuel gauge having a main body and a sensor for detecting a relative position of the arm with respect to the main body is widely used. The vehicle is provided with fuel remaining amount display means for displaying the remaining amount of fuel corresponding to the relative position of the arm to the main body detected by the sensor so as to be visible to the driver. Furthermore, various configurations for detecting that an abnormality such as a fuel leak has occurred in a fuel tank using a measurement value obtained by the fuel gauge are also known (see, for example, Patent Document 1).

  By the way, in a vehicle equipped with this type of fuel tank, conventionally, only a measured value by a fuel gauge has been used to detect that an abnormality such as fuel leakage has occurred in the fuel system. For example, in the configuration described in Patent Document 1, the measurement value obtained by the fuel gauge when the operation of the internal combustion engine is stopped is compared with the measurement value obtained by the fuel gauge when the operation of the internal combustion engine is restarted. Is determined to be that an abnormality has occurred in the fuel system.

  However, the abnormalities that can occur in the fuel system are not limited to fuel leakage. For example, there may be a deviation between the remaining amount of fuel and the measured value by the fuel gauge due to deformation of the fuel tank, or malfunction of the fuel gauge arm. For example, various values such as a value measured by the fuel gauge may be output as a value larger than the actual remaining amount of fuel. However, when the control using only the measurement value by the conventional fuel gauge is performed, it is difficult to understand what kind of abnormality is actually occurring in the fuel system, and it takes time and effort to identify the failure point. there were.

JP 2010-48204 A

  The present invention focuses on the above points, and an object of the present invention is to provide means for making it possible to more accurately determine the location of a fuel tank failure.

In order to solve the above problems, the control device for an internal combustion engine according to the first aspect of the present invention has a configuration as described below. That is, the control device for an internal combustion engine according to the first aspect of the invention is used to control an internal combustion engine having a fuel tank having a fuel gauge for measuring the remaining amount of fuel, and integrates the fuel injection amount. The fuel supply amount is calculated, and the fuel consumption amount is calculated based on the measured value by the fuel gauge. When the difference between the fuel supply amount and the fuel consumption amount is a predetermined value or more, an abnormality occurs in the fuel tank. a control apparatus for an internal combustion engine that performs control to determine that is, with determining the fuel leakage is likely to have occurred when the fuel consumption is the predetermined value or more larger than the fuel supply amount Control for determining that there is a possibility that a shape abnormality has occurred in the fuel tank when the rate of change of the fuel supply amount relative to the fuel consumption amount is not constant and the fuel consumption amount is greater than the fuel supply amount. .
According to a second aspect of the present invention, there is provided a control device for an internal combustion engine, which is used for controlling an internal combustion engine having a fuel tank having a fuel gauge for measuring a remaining amount of fuel, and integrating the fuel injection amount. The fuel supply amount is calculated, and the fuel consumption amount is calculated based on the measured value by the fuel gauge. When the difference between the fuel supply amount and the fuel consumption amount is equal to or greater than a predetermined value, there is an abnormality in the fuel tank. A control device for an internal combustion engine that performs control to determine that the fuel has occurred, and a fuel tank when a rate of change of the fuel supply amount with respect to the fuel consumption amount is not constant and the fuel consumption amount is greater than the fuel supply amount Control is performed to determine that there is a possibility that a shape abnormality has occurred.

In such a case, referring to not only the fuel consumption based on the measurement value by the fuel gauge but also the fuel supply amount, the difference between the fuel consumption amount and the fuel supply amount, and the rate of change between them. Based on the above, it is possible to more accurately determine the failure location of the fuel system.
In the invention of claim 1, since it is determined that there is a possibility of fuel leakage when the fuel consumption is greater than the fuel supply amount by the predetermined value or more, diagnosis of fuel leakage is effectively performed. It can be carried out. This is because when a problem other than fuel leakage occurs, the fuel consumption cannot exceed the fuel supply amount regardless of the remaining amount of fuel.
Further, in any of the first and second aspects of the invention, when the rate of change of the fuel supply amount with respect to the fuel consumption amount is not constant and the fuel consumption amount is larger than the fuel supply amount, a shape abnormality occurs in the fuel tank. Therefore, it is possible to effectively diagnose the abnormality in the shape of the fuel tank. This is because if a depression (upwardly convex deformation) occurs in the lower part of the fuel tank, the amount of liquid level drop per actual fuel consumption increases when the remaining amount of fuel decreases.

  In the present invention, the “fuel tank” is not limited to the fuel tank main body and the fuel gauge for storing fuel, but is used for supplying the fuel stored in the fuel tank main body toward the injector. It is the concept which shows the whole fuel supply system containing a fuel pump. The “difference between fuel consumption and fuel supply” is a concept that includes both the difference and the ratio between them.

  ADVANTAGE OF THE INVENTION According to this invention, the means for determining more correctly the failure location of a fuel tank can be provided.

1 is a diagram schematically showing an internal combustion engine according to an embodiment of the present invention. The figure which shows schematically the fuel tank which concerns on the same embodiment. The figure which shows roughly the fuel consumption and fuel supply quantity which concern on the same embodiment. The flowchart which shows the example of a procedure of the process which the control apparatus of the embodiment performs. The figure which shows schematically the relationship between the fuel consumption and fuel supply quantity which concern on the same embodiment.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, the vehicle according to the present embodiment includes an engine E that is an internal combustion engine, and a fuel tank 5 that stores fuel supplied to the engine E.

  The engine E is a spark ignition gasoline engine, and includes a plurality of cylinders 1 (one of which is shown in FIG. 1). In the vicinity of the intake port of each cylinder 1, an injector 11 for injecting fuel is provided. A spark plug 12 is attached to the ceiling of the combustion chamber of each cylinder 1. The spark plug 12 receives spark voltage generated by the ignition coil and causes spark discharge between the center electrode and the ground electrode. The ignition coil is integrally incorporated in a coil case together with an igniter that is a semiconductor switching element.

  The intake passage 3 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 1. On the intake passage 3, an air cleaner 31, an electronic throttle valve 32, a surge tank 33, and an intake manifold 34 are arranged in this order from the upstream.

  The exhaust passage 4 for discharging the exhaust guides the exhaust generated as a result of burning the fuel in the cylinder 1 from the exhaust port of each cylinder 1 to the outside. An exhaust manifold 42 and an exhaust purification three-way catalyst 41 are disposed on the exhaust passage 4.

  On the other hand, as shown in FIG. 2, the fuel tank 5 includes a fuel tank main body 51 and a fuel pump 52 for supplying fuel stored in the fuel tank main body 51 toward the injector 11. A float 53a which is provided inside the fuel tank main body 51 and moves up and down following the fuel level, an arm 53b having a tip connected to the float 53a, and a pivot 53c which pivotally supports the base end of the arc 53b. And a fuel gauge 53 as a fuel remaining amount detecting element formed by using a sensor main body 53d for detecting the position of the arm 53b. The float 53a and the arm 53b of the fuel gauge 53 detect the remaining amount of fuel as shown by the solid line in FIG. 2 from the highest liquid level when the tank is full as shown by the imaginary line in FIG. It is possible to move up and down to the lowest liquid level that is the liquid level when the predetermined value is the limit. The fuel gauge 53 outputs a liquid level signal g indicating the fuel liquid level to the ECU 0 serving as a control device. The value of the liquid level signal g is “5 (F)”, “4”, “3”, “2”, “1”, “0”, and “E” in order from the highest fuel level. One of seven types.

ECU (Electronic Control) which is a control device of the internal combustion engine of the present embodiment
(Unit) 0 is a microcomputer system having a processor, a memory, an input interface, an output interface, and the like.

The input interface includes a vehicle speed signal a output from a vehicle speed sensor that detects the actual vehicle speed of the vehicle, a crank angle signal (N signal) b output from an engine rotation sensor that detects the rotation angle of the crankshaft and the engine speed, An accelerator opening signal c output from a sensor that detects the amount of depression of the accelerator pedal or the opening of the throttle valve 32 as an accelerator opening, and an intake air temperature and an intake pressure in the intake passage 3 (particularly, the surge tank 33) are detected. The intake air temperature / intake pressure signal d output from the temperature / pressure sensor, the coolant temperature signal e output from the water temperature sensor for detecting the engine coolant temperature, and the O ₂ for detecting the air-fuel ratio of the exhaust gas upstream of the catalyst 41. An air-fuel ratio signal f output from the sensor 43, a liquid level signal g output from the fuel gauge 53, an intake camshaft or an exhaust cam A cam angle signal output from cam angle sensor at a plurality of cam angle of Yafuto (G signal) h or the like is input.

  From the output interface, an ignition signal i is output to the igniter of the spark plug 12, a fuel injection signal j is output to the injector 11, an opening operation signal k is output to the throttle valve 32, and the like.

  The processor of the ECU 0 interprets and executes a program stored in advance in the memory, calculates operation parameters, and controls the operation of the engine E. The ECU 0 acquires various information a, b, c, d, e, f, g, and h necessary for operation control of the engine E through the input interface, knows the engine speed, and is filled in the cylinder 1. Estimate the intake volume. Then, operating parameters such as required fuel injection amount, fuel injection timing (including the number of times of fuel injection for one combustion), fuel injection pressure, and ignition timing are determined. As the operation parameter determination method itself, a known method can be adopted. The ECU 0 applies various control signals i, j, and k corresponding to operation parameters and user operations via an output interface.

  Therefore, in the present embodiment, the processor of the ECU 0 executes the following fuel tank abnormality determination program in order to determine the occurrence of the fuel tank abnormality. That is, the measured value by the fuel gauge 53, in other words, the fuel consumption amount Al corresponding to the fuel level indicated by the level signal g as shown in FIG. 3 and the fuel injection amount F as shown in FIG. The fuel supply amount B1 calculated in this way is compared, and it is determined that an abnormality has occurred in the fuel tank 5 when the difference Δl between the fuel supply amount B1 and the fuel consumption amount Al is greater than or equal to a predetermined value. Control. In this fuel tank abnormality determination program, the fuel supply amount B1 is integrated every time fuel is injected by the injector 11. Further, the comparison between the fuel consumption amount Al and the fuel supply amount Bl is performed when the value of the liquid level signal g changes. Further, the integration of the fuel supply amount Bl is started with reference to the time when the fuel level indicated by the liquid level signal g rises and the value of the liquid level signal g becomes “4” or more. The fuel consumption amount Al is based on the remaining amount of fuel indicated by the value of the liquid level signal g when the integration of the fuel supply amount B1 is started.

  Hereinafter, a control procedure performed by the processor executing this fuel tank abnormality determination program will be described below with reference to FIG. 4 which is a flowchart.

First, a new fuel supply amount Bl is calculated by adding the current fuel injection amount F to the previous fuel supply amount Bl (step S1). Next, a fuel consumption amount Al corresponding to the fuel level indicated by the level signal g is obtained (step S2). Then, when the liquid level signal g changes to the side where the liquid level decreases compared to the previous time (step S3), the difference Δl is calculated by subtracting the fuel supply amount Bl from the fuel consumption amount Al. (Step S4) If the difference Δl is positive and greater than or equal to the predetermined value Δl ₀ (Step S5), information indicating that there is a possibility of fuel leakage is written in a predetermined location in the memory (Step S6). ). Further, the ratio of the increase degree of the fuel consumption amount Al to the increase degree of the fuel supply amount Bl is not constant (step S7), and the difference Δl obtained by subtracting the fuel supply amount Bl from the fuel consumption amount Al is positive. In the case of (Step S8), information indicating that there is a possibility that a shape abnormality has occurred in the fuel tank is written in a predetermined location of the memory (Step S9). On the other hand, the ratio of the increase in the fuel consumption Al to the increase in the fuel supply B1 is not constant (step S7), and the difference Δl obtained by subtracting the fuel supply B1 from the fuel consumption Al is negative. In the case of (Step S8), information indicating that there is a possibility that an abnormality has occurred in the fuel gauge 53 is written in a predetermined location of the memory (Step S10). The predetermined value Δl ₀ is set to a value sufficiently larger than an amount that can be caused by an error in the fuel injection amount from the injector 11. Note that when the engine E is stopped, the values of the fuel consumption amount Al and the fuel supply amount Bl at that time are written in predetermined locations in the memory, and the values of the fuel consumption amount Al and the fuel supply amount Bl when restarting. Is read out.

  That is, according to the present embodiment, not only the fuel consumption amount Al based on the measured value by the fuel gauge 53 but also the fuel supply amount Bl is referred to, the difference Δl between the fuel consumption amount Al and the fuel supply amount Bl, and these By calculating the rate of change between the two, the failure location of the fuel tank 5 can be determined more accurately.

In particular, as shown by a solid line a in FIG. 5, since when the fuel consumption Al predetermined value .DELTA.l ₀ or greater than the fuel supply amount Bl is determined that there is a possibility that fuel leakage has occurred, the fuel The occurrence of leakage can be determined more accurately.

  Further, when a dent (upwardly convex deformation) is generated in the lower portion of the fuel tank 5, when the remaining amount of fuel decreases, the liquid per actual fuel supply amount Bl as shown by the solid line b in FIG. Focusing on the fact that the amount of surface decrease increases, if the rate of change of the fuel supply amount Bl with respect to the fuel consumption amount Al is not constant and the fuel consumption amount Al is greater than the fuel supply amount Bl, the fuel consumption amount per Al Since it is determined that there is a possibility that the liquid level lowering amount is large, it is possible to determine the shape abnormality of the fuel tank 5 more accurately.

  Except when an abnormality occurs in the fuel gauge 53, the fuel consumption amount Al indicated by the output value of the fuel gauge 53 cannot be smaller than the fuel supply amount Bl as shown by the solid line c in FIG. When the change rate of the fuel supply amount Bl with respect to the fuel consumption amount Al is not constant and the fuel consumption amount Al is less than the fuel supply amount Bl, there is a possibility that an abnormality has occurred in the fuel gauge 53. Since it is determined that there is, it is possible to determine the abnormality of the fuel gauge 53 more accurately.

  The present invention is not limited to the embodiment described above.

  For example, in the above-described embodiment, the abnormality of the fuel tank is detected based on the difference between the fuel consumption amount and the fuel supply amount, but the fuel tank abnormality is detected based on the ratio of the fuel consumption amount and the fuel supply amount. Of course, it may be detected.

  In addition to writing information in the memory indicating the occurrence of fuel leaks, fuel tank shape abnormalities, and fuel gauge abnormalities, the driver can be informed by light and sound typified by separate indicator lights. You may make it notify a driver | operator of generation | occurrence | production of abnormality using the means for notifying.

  Furthermore, the timing for starting the integration of the fuel supply amount is not limited to that described in the above-described embodiment, and may be arbitrarily set.

  In addition, various changes may be made without departing from the spirit of the present invention.

E ... Internal combustion engine
0 ... Control unit (ECU)
5 ... Fuel tank 53 ... Fuel gauge Al ... Fuel consumption Bl ... Fuel supply amount

Claims (2)

Used to control an internal combustion engine with a fuel tank with a fuel gauge for measuring the remaining amount of fuel ;
Calculate the fuel supply amount by integrating the fuel injection amount,
Calculate the fuel consumption based on the measured value by the fuel gauge,
The difference between the fuel consumption and the fuel supply amount A control apparatus for an internal combustion engine that performs control to determine that the abnormality in the fuel tank is equal to or greater than a predetermined value is generated,
When it is determined that there is a possibility of fuel leakage when the fuel consumption is greater than the fuel supply amount by the predetermined value or more,
An internal combustion engine that performs control to determine that there is a possibility that a shape abnormality has occurred in the fuel tank when the rate of change of the fuel supply amount with respect to the fuel consumption amount is not constant and the fuel consumption amount is greater than the fuel supply amount Engine control device. Used to control an internal combustion engine with a fuel tank with a fuel gauge for measuring the remaining amount of fuel;
Calculate the fuel supply amount by integrating the fuel injection amount,
Calculate the fuel consumption based on the measured value by the fuel gauge,
A control device for an internal combustion engine that performs control to determine that an abnormality has occurred in a fuel tank when a difference between the fuel supply amount and the fuel consumption amount is a predetermined value or more,
An internal combustion engine that performs control to determine that there is a possibility that a shape abnormality has occurred in the fuel tank when the rate of change of the fuel supply amount with respect to the fuel consumption amount is not constant and the fuel consumption amount is greater than the fuel supply amount Engine control device.

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