Vehicle control device

Abstract

To provide a control device of a vehicle capable of suppressing inflow of water from an exhaust pipe to an internal combustion engine and indicating a river limit, in the vehicle performing intermittent operation.SOLUTION: A control device for a vehicle according to the present disclosure is a control device for a vehicle including an internal combustion engine configured to output a driving force for traveling, the control device including a detection unit configured to detect a back pressure of the internal combustion engine during idle operation, and a determination unit configured to determine whether or not to prohibit intermittent stop control of the internal combustion engine based on the detected back pressure and a threshold of the back pressure.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a vehicle control device. [Background technology]

[0002] It is expected that a part of a vehicle will become submerged in water when crossing a river, etc. Patent Document 1 discloses a technology related to an engine air-fuel ratio control device that prohibits deterioration detection of an air-fuel ratio sensor provided in an exhaust system of an internal combustion engine mounted on a vehicle when the air-fuel ratio sensor is submerged in water. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-42590 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when an intermittently operated vehicle stops intermittently in water, water may flow into the engine's combustion chamber from the exhaust pipe, causing a water hammer phenomenon. Furthermore, since it is difficult for the driver to recognize that the vehicle is underwater, vehicles prohibited from intermittent stopping cannot indicate to the driver the river crossing limit. Therefore, when an intermittently operated vehicle crosses a river, it is preferable to prevent water from flowing into the internal combustion engine from the exhaust pipe.

[0005] The present invention aims to provide a vehicle control device that can suppress the inflow of water from the exhaust pipe into the internal combustion engine when a vehicle operating intermittently crosses a river, and that can indicate the river crossing limit. [Means for solving the problem]

[0006] The vehicle control device of the present invention is a control device for a vehicle equipped with an internal combustion engine that outputs driving force for driving, and includes a detection unit that detects the back pressure of the internal combustion engine during idling, and a judgment unit that determines whether to prohibit intermittent stop control of the internal combustion engine based on the detected back pressure and a threshold value of the back pressure. [Effects of the Invention]

[0007] The present invention provides a vehicle control device that can suppress the inflow of water from the exhaust pipe into the internal combustion engine when a vehicle operating intermittently crosses a river, and that can indicate the river crossing limit. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing a configuration of a vehicle according to an embodiment of the present invention; [Figure 2] 3 is a flowchart showing the procedure of a process executed by a control device for a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described with reference to the drawings. Note that the drawings are simplified, and the technical scope of the embodiments should not be narrowly interpreted based on the description in the drawings. Furthermore, identical elements are given the same reference numerals, and redundant explanations will be omitted. Furthermore, in the following embodiments, when referring to the number of elements (including the number, numerical value, amount, range, etc.), unless otherwise specified or when it is clearly limited to a specific number in principle, it is not limited to that specific number, and may be more or less than the specific number.

[0010] Furthermore, in the following embodiments, the components are not necessarily essential unless otherwise specified or considered to be clearly essential in principle. Similarly, in the following embodiments, when referring to the shape, positional relationship, etc. of the components, etc., it is intended to include those that are substantially similar or similar to the shape, etc., unless otherwise specified or considered to be clearly not essential in principle. The same applies to the above numbers, etc. (including numbers, numerical values, amounts, ranges, etc.).

[0011] <Embodiment> Fig. 1 is a diagram showing the configuration of a vehicle 10 according to one embodiment of the present invention. The vehicle 10 shown in Fig. 1 is capable of running by driving force generated by an engine 20. The vehicle 10 is configured to run while the engine 20 is operating intermittently.

[0012] As shown in FIG. 1, a vehicle 10 includes an engine 20, an exhaust pipe 30, an ECU (Electronic Control Unit) 40, and an intake pipe 50.

[0013] The engine 20 is an example of an "internal combustion engine." In the engine 20, a mixture of fuel and air is burned in a combustion chamber 21, and pistons reciprocate within the combustion chamber 21, thereby rotating a crankshaft and outputting driving force for running the vehicle from the crankshaft. The engine 20 includes a surge tank 22 and an exhaust manifold 23.

[0014] The surge tank 22 is connected between the intake pipe 50 and each intake port of the engine 20. The surge tank 22 temporarily stores air and supplies it to each intake port of the engine 20. The exhaust manifold 23 collects and discharges exhaust gases discharged from each exhaust port of the engine 20. An injector 24 is provided at each intake port of the engine 20. The injector 24 injects fuel into the intake port of the engine 20 under the control of the ECU 40.

[0015] The intake pipe 50 is an intake passage for air drawn into the engine 20. The intake pipe 50 is connected to the surge tank 22 of the engine 20. A throttle valve 51 and an intercooler 52 are provided in the intake pipe 50. The throttle valve 51 adjusts the amount of air drawn into the engine 20 by opening and closing inside the intake pipe 50. The intercooler 52 cools the intake air flowing through the intake pipe 50 with cooling water.

[0016] An air cleaner 53 is provided in the intake pipe 50. The air cleaner 53 removes foreign matter from the intake air. The intake pipe 50 is also provided with an air bypass passage 54.

[0017] An air bypass valve 55 is provided in the air bypass passage 54. The air bypass valve 55 adjusts the flow rate of air flowing through the air bypass passage 54 by opening and closing under the control of the ECU 40.

[0018] The exhaust pipe 30 is an exhaust passage for discharging exhaust gas. A first catalyst 31 and a second catalyst 32 are provided in the exhaust pipe 30.

[0019] The first catalyst 31 is provided in the exhaust pipe 30. The second catalyst 32 is provided in the exhaust pipe 30, downstream of the first catalyst 31. The first catalyst 31 and the second catalyst 32 purify the exhaust gas flowing through the exhaust pipe 30. For example, the first catalyst 31 has a casing with a hollow structure and a catalyst carrier housed in the casing. The catalyst carrier is, for example, a honeycomb structure made of a ceramic material such as cordierite, and supports a catalytic substance for purifying HC (hydrocarbons), CO (carbon monoxide), and NOx (nitrogen oxides) contained in the exhaust gas flowing through the exhaust pipe 30.

[0020] The exhaust pipe 30 is also provided with a bypass passage 33. The bypass passage 33 connects the exhaust manifold 23 and the exhaust pipe 30. A wastegate valve 34 is provided in the bypass passage 33. The wastegate valve 34 opens and closes under the control of the ECU 40 to adjust the flow rate of exhaust gas flowing through the bypass passage 33. A backpressure sensor 35 is capable of measuring the pressure of exhaust gas in the exhaust pipe 30, and inputs the measured gas pressure to the ECU 40.

[0021] The ECU 40 is an example of a "vehicle control device." The ECU 40 controls the entire vehicle 10. For example, the ECU 40 can control the ignition timing, the opening of the throttle valve 51, the fuel injection amount and fuel injection timing of the injector 24, the gear ratio of the automatic transmission 60, the opening of the wastegate valve 34, the opening of the air bypass valve 55, etc.

[0022] ECU 40 includes a detection unit 41 and a determination unit 42. Detection unit 41 detects the back pressure of engine 20 during idling. The back pressure is detected by back pressure sensor 35. Determination unit 42 determines whether or not to prohibit intermittent stop control of engine 20 based on the detected back pressure and a back pressure threshold value.

[0023] More specifically, if the back pressure of the engine 20 is equal to or less than a first threshold, the determination unit 42 determines that the vehicle 10 is on land and permits intermittent stop control. Furthermore, if the back pressure is greater than the first threshold and equal to or less than a second threshold, the determination unit 42 determines that the vehicle 10 is in water that is deep enough to ford, and prohibits intermittent stop control. Furthermore, if the back pressure is greater than the second threshold, the determination unit 42 determines that the vehicle 10 is in water that is deeper than the water that is deep enough to ford, and prohibits intermittent stop control while warning the driver of the vehicle 10 not to drive in water that is deeper than this. The vehicle 10 may be provided with an audio or visual notification means for warning the driver.

[0024] The ECU 40 includes a CPU (Central Processing Unit) and various memories (e.g., a ROM (Read Only Memory) and a RAM (Random Access Memory)). The ECU 40 realizes various functions of the ECU 40 by the CPU executing programs stored in the various memories.

[0025] FIG. 2 is a flowchart showing the procedure of processing executed by the ECU 40, which is a control device for a vehicle according to one embodiment of the present invention.

[0026] First, when the engine power requirement of the vehicle 10 reaches 0 kW (S101), the vehicle 10 starts idling (S102). At this time, the detection unit 41 of the ECU 40 detects the back pressure a of the engine 20 during idling (S103). The back pressure a is detected by the back pressure sensor 35.

[0027] If the back pressure a of the engine 20 is equal to or less than the first threshold value p (Yes in S104), the determination unit 42 determines that the vehicle 10 is on land and makes a determination to permit the intermittent stop control (S105). If the back pressure a of the engine 20 is greater than the first threshold value p (No in S104), the determination unit 42 makes a determination to prohibit the intermittent stop control (S106).

[0028] If the back pressure a of the engine 20 is greater than the first threshold p and equal to or less than the second threshold q (Yes in S107), the determination unit 42 determines that the vehicle 10 is in water that is deep enough to ford, prohibits intermittent stop control, and does not issue a warning to the driver of the vehicle 10 (S108). Furthermore, if the back pressure a is greater than the second threshold q (No in S107), the determination unit 42 determines that the vehicle 10 is in water that is deeper than the water that is deep enough to ford, prohibits intermittent stop control, and warns the vehicle not to drive in water that is deeper than the water that is deep enough to ford (S109).

[0029] <Effects of the vehicle control device according to this embodiment> The ECU 40 according to this embodiment, i.e., the vehicle control device, detects the back pressure of the engine 20, which is an internal combustion engine. If it is determined that the vehicle 10 is fording a river based on the back pressure of the engine 20 and a back pressure threshold, the intermittent stop control is prohibited. In other words, because the engine 20 does not stop while underwater, it is possible to suppress the inflow of water from the exhaust pipe 30 into the engine 20 and maintain the fording performance. It is also possible to determine that the vehicle 10 is in a position deeper than the fordable water depth, and in that case, it is possible to warn the driver of the vehicle 10 not to drive further into deeper water.

[0030] The present invention has been described above in accordance with the above-mentioned embodiments, but the present invention is not limited to the configurations of the above-mentioned embodiments, and naturally includes various modifications, alterations, and combinations that can be made by a person skilled in the art within the scope of the invention claimed in the claims of this application. [Explanation of symbols]

[0031] 10 vehicles 20 Engine (internal combustion engine) 30 exhaust pipe 35 Back pressure sensor 40 ECU (vehicle control unit) 41 Detector 42 Judgment section 50 intake pipe

Claims

[Claim 1] A control device for a vehicle equipped with an internal combustion engine that outputs driving force for traveling, a detection unit that detects a back pressure of the internal combustion engine during idle operation; a determination unit that determines whether or not to prohibit intermittent stop control of the internal combustion engine based on the detected back pressure and a threshold value of the back pressure; A vehicle control device comprising:

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