Driving sound determination device

Abstract

Provided is a drive sound determination device capable of determining whether or not the drive sound of a diesel engine is caused by resonance sound. A drive sound determination device is provided with: a measurement unit that measures the drive sound of a diesel engine; a first calculation unit that calculates a driving sound frequency, which is the frequency of the driving sound; a second calculation unit that calculates a resonance frequency, which is the frequency of a resonance sound caused by combustion pressure in a cylinder of the diesel engine, on the basis of information relating to the type of the diesel engine and information relating to the operating state of the diesel engine; and a determination unit that determines whether or not the driving sound is caused by the resonance sound on the basis of the driving sound frequency and the resonance frequency.

Description

TECHNICAL FIELD

[0001] The present application relates to a drive sound determination device. BACKGROUND

[0002] There is a technology that suppresses a resonance sound caused by a combustion pressure in a cylinder of a diesel engine (for example, refer to Patent Literature 1).

[0003] [Patent Literature 1] Japanese Patent Application Publication No. 2019-060264 SUMMARY PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] It is difficult to determine whether a drive sound of a diesel engine is caused by the above-described resonance sound or by a failure other than that.

[0005] Therefore, an object of the present application is to provide a drive sound determination device capable of determining whether a drive sound of a diesel engine is caused by a resonance sound. MEANS FOR SOLVING THE PROBLEMS

[0006] The above object is achieved by a drive sound determination device including: a measurement unit that measures a drive sound of a diesel engine; a first calculation unit that calculates a frequency of the drive sound, that is, a drive sound frequency; a second calculation unit that calculates a frequency of a resonance sound caused by a combustion pressure in a cylinder of the diesel engine, that is, a resonance frequency, based on information related to a model of the diesel engine and information related to an operating state of the diesel engine; and a determination unit that determines whether the drive sound is caused by the resonance sound based on the drive sound frequency and the resonance frequency. EFFECTS OF THE INVENTION

[0007] According to the present application, it is possible to provide a drive sound determination device capable of determining whether a drive sound of a diesel engine is caused by a resonance sound. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is a schematic configuration diagram of a drive sound determination system. Figure 2 is a flowchart illustrating drive sound determination control. DETAILED DESCRIPTION

[0009] [Outline configuration of drive sound determination system] Figure 1is a schematic configuration diagram of a drive sound determination system 100. The drive sound determination system 100 includes a vehicle A and a determination terminal 40. The vehicle A is equipped with an engine system B. The engine system B will be described later in detail, and includes a diesel engine 1, an ECU (Electronic Control Unit) 20, and a dongle 21. The ECU 20 is a computer including a CPU (Central Processing Unit), a storage device. The ECU 20 controls driving of the diesel engine 1.

[0010] The dongle 21 is configured as a communication device equipped with a wireless communication module. The dongle 21 is mounted on a connection terminal provided below a steering wheel, for example. The connection terminal is connected to the ECU 20. The dongle 21 wirelessly transmits information related to the vehicle A from the ECU 20 to the determination terminal 40.

[0011] The determination terminal 40 is configured as a portable terminal that a worker of a vehicle sales shop or a worker of a repair factory can carry. The determination terminal 40 is a smartphone or a tablet, for example, and is an example of a drive sound determination device. The determination terminal 40 is provided with a CPU 42, a storage device 44, a display 46, a touch panel 48, a speaker 50, a microphone 52, and a camera 54. They are capable of communicating with each other via a communication line 58. The storage device 44 is a nonvolatile memory that is electrically rewritable.

[0012] The storage device 44 stores a drive sound determination program 44a therein. The drive sound determination program 44a is a program for causing the determination terminal 40 to function as a device that determines whether a drive sound of the diesel engine 1 of the vehicle A is caused by a resonance sound. The CPU 42 executes drive sound determination control in accordance with the drive sound determination program 44a by functionally realizing a measurement section, a first calculation section, a second calculation section, and a determination section, which will be described later in detail. The display 46 is configured by an LCD, an LED, or the like, for example. The touch panel 48 is overlaid on the display 46.

[0013] [Drive sound determination control] Figure 2 is a flowchart showing an example of the drive sound determination control. Note that this control is assumed to be executed by an examiner operating the determination terminal 40 in the vicinity of or inside a parked vehicle A in a state where the diesel engine 1 is driven. In addition, this control is executed by the CPU 42 in accordance with the drive sound determination program 44a.

[0014] First, the CPU 42 measures a drive sound of the vehicle A via the microphone 52 (step S1). Step S1 is an example of processing executed by the measurement section. Next, the CPU 42 calculates a frequency of the measured drive sound (step S2). Step S2 is an example of processing executed by the first calculation section.

[0015] Next, the CPU 42 reads the engine model-related information and the operation state-related information of the diesel engine 1 via the dongle 21 (step S3). The engine model-related information of the diesel engine 1 is, for example, the model number, serial number of the diesel engine. The operation state-related information of the diesel engine 1 includes, for example, the engine speed, state of fuel injection, intake air amount, oil / water temperature, intake air temperature, state of variable valve system, gear of transmission, remaining capacity of battery, pressure values of various sensors, temperature values, and the like.

[0016] Next, the CPU 42 determines whether the diesel engine 1 is in an operation state in which fuel injection is being performed, based on the above information (step S4). That is, it is determined whether fuel cut is performed.

[0017] In the case where the determination in step S4 is "Yes", the CPU 42 refers to a table that defines the combustion gas temperature corresponding to the engine speed and fuel injection amount, to estimate the combustion gas temperature (step S5).

[0018] Next, the CPU 42 calculates the frequency of the sympathetic sound caused by the combustion pressure in the cylinder of the diesel engine 1, that is, the sympathetic frequency (step S6). The sympathetic frequency is proportional to the speed of sound in the combustion chamber, and is inversely proportional to the cylinder diameter and the combustion chamber diameter. The CPU 42 calculates the estimated combustion gas temperature and the sympathetic frequency at the combustion gas temperature set for each engine model of the diesel engine 1. Step S6 is an example of the processing performed by the second calculating section.

[0019] Next, the CPU 42 determines whether the driving sound frequency is within the range of the sympathetic frequency (step S7).

[0020] In the case where the determination in step S7 is "Yes", it is determined that the cause of the driving sound is the combustion pressure sympathetic vibration in the diesel engine 1 (step S8). In this case, the display 46 displays that the cause of the driving sound is the combustion pressure sympathetic vibration in the diesel engine 1. Step S8 is an example of the processing performed by the determining section.

[0021] In the case where the determination in step S4 or S7 is "No", it is determined that the cause of the driving sound is other than the combustion pressure sympathetic vibration in the diesel engine 1 (step S9). The display 46 displays that the cause of the driving sound is other than the combustion pressure sympathetic vibration in the diesel engine 1.

[0022] As described above, by using the determining terminal 40 in which the driving sound determining program 44a is installed, it is possible to accurately determine whether the driving sound of the diesel engine 1 is based on the sympathetic sound. Thus, even if the determiner is a person who has no insight into abnormal sounds, it is possible to easily determine the cause of the driving sound. In addition, by installing the driving sound determining program 44a in the determining terminal 40, it is possible to realize such determination at low cost.

[0023] The above detailed the embodiments of the present application, but the present application is not limited to the specific embodiments, and various modifications and changes can be made within the scope of the gist of the present application recited in the claims. Explanation of Reference Signs

[0024] A vehicle 1 Diesel engine 40 Determination terminal (driving sound determination device, measurement section, first calculation section, second calculation section, determination section).

Claims

1. A driving sound determination device, comprising: The measurement department measures the drive sound of diesel engines; The first calculation unit calculates the frequency of the driving sound, i.e., the driving sound frequency. The second calculation unit calculates the frequency of the resonance sound caused by the combustion pressure in the cylinder of the diesel engine, i.e., the resonance frequency, based on the engine model-related information and the operating status-related information of the diesel engine. and The determination unit determines, based on the driving sound frequency and the resonance frequency, whether the driving sound is caused by the resonance sound.

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