Oil change notification method

Abstract

To make a notification of necessity of replacement of oil at appropriate timing.SOLUTION: In an oil replacement notification method for making a notification of necessity of replacement of oil for lubricating an engine mounted to a vehicle, a current traveling pattern is determined on the basis of vehicle speed, engine speed and an engine load factor, and a precursor accumulation amount as an accumulation amount per unit time of a sludge precursor accumulated in oil is calculated on the basis of a calculation formula different for each traveling pattern and a fuel consumption amount of the engine. When an integrated amount of the calculated precursor accumulation amount is a predetermined amount or greater, a notification of the necessity of replacement of the oil is made.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an oil change notification method. [Background technology]

[0002] A method for determining deterioration of oil that lubricates an engine has been proposed (see, for example, Patent Document 1). This method calculates the cumulative amount of sludge precursors accumulated in the oil, and determines that the oil has deteriorated when the cumulative amount of sludge precursors is equal to or greater than a first determination threshold based on vehicle use location information, or when the cumulative amount of sludge precursors corrected based on use location information is equal to or greater than a second determination threshold that is not based on use location. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-29200 Summary of the Invention [Problem to be solved by the invention]

[0004] The above-mentioned method may not be able to accurately determine oil deterioration. The degree of oil deterioration varies depending on the vehicle's driving pattern, but the above-mentioned method may not be able to accurately determine oil deterioration because it does not take driving pattern into consideration. If the oil deterioration cannot be accurately determined, it will be impossible to notify the driver that an oil change is necessary at the appropriate time.

[0005] The oil change notification method of the present invention has a main object to notify the driver that an oil change is necessary at an appropriate time. [Means for solving the problem]

[0006] The oil change notification method of the present invention employs the following means to achieve the above-mentioned main object.

[0007] The oil change notification method of the present invention is an oil change notification method that notifies the driver that the oil lubricating the engine mounted on a vehicle needs to be changed, and includes the steps of: determining a current driving pattern based on the vehicle speed, the engine rotation speed, and the engine load factor; calculating a precursor accumulation amount as the amount of sludge precursors accumulated in the oil per unit time based on a calculation formula that differs for each driving pattern and the engine's fuel consumption; and notifying the driver that the oil needs to be changed when the calculated cumulative amount of precursor accumulation is equal to or greater than a predetermined amount. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing an outline of the configuration of an oil change notification system (oil change notification system) 10 that executes an oil change notification method according to one embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing the outline of the configuration of an engine 22. [Figure 3] 4 shows an example of a notification processing routine executed by the ECU 70. DETAILED DESCRIPTION OF THE INVENTION

[0009] Next, a mode for carrying out the present invention will be described using examples. [Example]

[0010] Fig. 1 is a diagram showing the outline of the configuration of an oil change notification system (oil change notification system) 10 that executes an oil change notification method according to one embodiment of the present invention. Fig. 2 is a diagram showing the outline of the configuration of an engine 22 mounted on a hybrid vehicle 20. The oil change notification system 10 includes the hybrid vehicle 20, a data server 90, and a mobile terminal 92.

[0011] As shown in FIG. 1, the hybrid vehicle 20 includes an engine 22, a motor 30, an inverter 32, a clutch K0, an automatic transmission 40, a high-voltage battery 60, a low-voltage battery 62, a DC / DC converter 64, and an electronic control unit (hereinafter referred to as "ECU") 70.

[0012] The engine 22 is configured as a six-cylinder internal combustion engine that outputs power using fuel such as gasoline or diesel. As shown in FIG. 2, the engine 22 has a port injection valve 126 that injects fuel into an intake port and an in-cylinder injection valve 127 that injects fuel into a cylinder. By having the port injection valve 126 and the in-cylinder injection valve 127, the engine 22 can operate in any of a port injection mode, an in-cylinder injection mode, and a combined injection mode. In the port injection mode, air purified by an air cleaner 122 is drawn into an intake pipe 123 and passes through a throttle valve 124 and a surge tank 125, and fuel is injected from a port injection valve 126 downstream of the surge tank 125 in the intake pipe 123 to mix the air and fuel. This air-fuel mixture is then drawn into combustion chamber 129 via intake valve 128, where it explodes and burns with the help of an electric spark from spark plug 130. The resulting energy pushes down piston 132 in the cylinder bore, and the reciprocating motion of piston 132 is converted into rotational motion of crankshaft 23. In in-cylinder injection mode, fuel is injected from in-cylinder injection valve 127 instead of port injection valve 126. In shared injection mode, fuel is injected from both port injection valve 126 and in-cylinder injection valve 127. These injection modes are switched based on the operating state of engine 22. Exhaust gas discharged from combustion chamber 129 into exhaust pipe 134 via exhaust valve 133 is discharged into the outside air via purification device 135, which has a purification catalyst (three-way catalyst) 135a, and PM filter 136, which collects particulate matter (PM) such as soot in the exhaust. The engine 22 is lubricated by lubricating oil (oil) stored in an oil pan (not shown) under the vehicle, supplied by a lubrication device (not shown). The lubricating oil supplied to the engine 22 passes through various parts of the engine 22 and returns to the oil pan. The operation of the engine 22 is controlled by the ECU 70.

[0013] As shown in FIG. 1 , a starter motor 25 for cranking the engine 22 and an alternator 26 for generating electricity using power from the engine 22 are connected to the crankshaft 23 of the engine 22. The starter motor 25 and the alternator 26, along with a low-voltage battery 62, are connected to a low-voltage power line 63. The motor 30 is configured as a synchronous generator motor, and a rotating shaft 31 to which a rotor is fixed is connected to the crankshaft 23 of the engine 22 via a clutch K0 and to an input shaft 41 of an automatic transmission 45. The inverter 32 is used to drive the motor 30 and is connected to the high-voltage power line 61. The motor 30 is rotationally driven by switching control of multiple switching elements of the inverter 32 by an ECU 70. The clutch K0 is configured as, for example, a hydraulically driven friction clutch, and connects and disconnects the crankshaft 23 of the engine 22 and the rotating shaft 31 of the motor 30. The automatic transmission 40 includes a torque converter 43 and, for example, a six-speed automatic transmission 45. The torque converter 43 is connected to an input shaft 41 connected to the rotary shaft 31 of the motor 30 and a transmission input shaft 44, which is the input shaft of the automatic transmission 45. The automatic transmission 45 is connected to the transmission input shaft 44 and an output shaft 42 connected to drive wheels 49 via a differential gear 48. Forward gears (first through sixth gears) and reverse gears are established by engaging and disengaging a plurality of friction engagement elements, and power is transmitted between the transmission input shaft 44 and the output shaft 42. The clutch K0 and the automatic transmission 45 are supplied with hydraulic oil whose pressure is adjusted by a hydraulic control device (not shown). The starter motor 25, the alternator 26, the clutch K0, and the hydraulic control device are controlled by an ECU 70.

[0014] High-voltage battery 60 is configured as, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery with a rated voltage of several hundred volts, and low-voltage battery 62 is configured as, for example, a lead-acid battery with a rated voltage of about 12 V or 14 V. DC / DC converter 64 is connected to high-voltage side power line 61 and low-voltage side power line 63.

[0015] The ECU 70 includes a microcomputer having a CPU, ROM, RAM, flash memory, input / output ports, and communication ports (not shown). Signals from various sensors are input to the ECU 70 via input ports. Examples of signals input to the ECU 70 include signals from various sensors required for controlling the operation of the engine 22, such as an intake air amount Qa from an air flow meter 123a attached upstream of the throttle valve 124 in the intake pipe 123, a crank angle θcr from a crank position sensor 140 detecting the rotational position of the crankshaft 23 of the engine 22, and a coolant temperature Tw from a water temperature sensor 142 detecting the temperature of the coolant for the engine 22. Other signals include various signals required for controlling the motor 30 and the automatic transmission 40, various signals for managing the high-voltage battery 60 and the low-voltage battery 62, and a vehicle speed V from a vehicle speed sensor 87. The ECU 70 outputs various control signals via output ports. The signals output from the ECU 70 include various control signals for controlling the operation of the engine 22, such as control signals for the throttle valve 124, port injection valve 126, in-cylinder injection valve 127, and spark plug 130, as well as control signals for the inverter 32, starter motor 25, alternator 26, clutch K0, automatic transmission 40 (hydraulic control device), and DC / DC converter 64. The ECU 70 calculates the rotation speed Ne of the engine 22 based on the crank angle θcr of the engine 22 from the crank position sensor 140. The engine ECU 24 also calculates a load factor KL (the ratio of the volume of air actually taken in during one cycle to the stroke volume per cycle of the engine 22) based on the intake air amount Qa from the air flow meter 123a and the rotation speed Ne of the engine 22.

[0016] In the hybrid vehicle 20 of the embodiment configured as described above, the ECU 70 controls the engine 22, the clutch K0, the motor 30, and the automatic transmission 40 so that the vehicle runs in a hybrid driving mode (HV driving mode) or an electric driving mode (EV driving mode). Here, the HV driving mode is a mode in which the clutch K0 is engaged and the vehicle runs using the power of the engine 22, and the EV driving mode is a mode in which the clutch K0 is disengaged and the vehicle runs without using the power of the engine 22.

[0017] The data server 90 is installed, for example, in an automobile dealership. The data server 90 is configured as a well-known computer and includes a CPU, ROM, RAM, a storage device (for example, an HDD or SSD), an input / output port, a communication port, etc. The data server 90 exchanges various information with the hybrid vehicle 20 via wireless communication.

[0018] The mobile terminal 92 is configured as, for example, a smartphone carried by the user of the hybrid vehicle 20. The mobile terminal 92 is configured as a well-known computer and includes a CPU, ROM, RAM, input / output ports, communication ports, etc. The mobile terminal 92 exchanges various information with the hybrid vehicle 20 via wireless communication.

[0019] Next, an operation of the change notification system 10 configured as described above when notifying a user to change the lubricating oil will be described. Fig. 3 is a flowchart showing an example of a notification processing routine executed by the ECU 70 of the hybrid vehicle 20. This routine is repeatedly executed at predetermined time intervals (for example, every few msec) while fuel injection is being performed in the engine 22.

[0020] When this routine is executed, the CPU of the ECU 70 inputs the cooling water temperature Tw detected by the water temperature sensor 142, the vehicle speed V detected by the vehicle speed sensor 87, the rotation speed Ne of the engine 22 calculated based on the crank angle θcr from the crank position sensor 140, and the load factor KL calculated based on the intake air amount Qa from the air flow meter 123a and the rotation speed Ne of the engine 22 (step S100).

[0021] Next, it is determined whether the vehicle speed V is less than a threshold value Vref1 (step S110), whether the vehicle speed V is less than a threshold value Vref2 that is lower than the threshold value Vref1 (step S120), whether the rotation speed Ne of the engine 22 is equal to or less than a threshold value Neref (step S130), and whether the load factor KL of the engine 22 is equal to or less than a threshold value KLref (step S140). Here, the threshold value Vref1 is a threshold value for determining whether the hybrid vehicle 20 is traveling at a high speed and is set to, for example, 75 km / h, 80 km / h, or 85 km / h. The threshold value Vref2 is a threshold value for determining whether the hybrid vehicle 20 is traveling at a low speed and is set to, for example, 40 km / h, 45 km / h, or 50 km / h. The threshold value Neref is a threshold value for determining whether the rotation speed of the engine 22 is low and is set to, for example, 2000 rpm, 2200 rpm, or 2400 rpm. The threshold value KLref is a threshold value for determining whether the load on the engine 22 is low or not, and is set to, for example, 35%, 40%, 45%, or the like.

[0022] In steps S110 to S140, if vehicle speed V is less than threshold value Vref1, vehicle speed V is less than threshold value Vref2, rotation speed Ne is equal to or less than threshold value Neref, and load factor KL is equal to or less than threshold value KLref, it is determined that hybrid vehicle 20 is traveling in a traffic jam, that is, traveling on a road where congestion has occurred, and constants a, b, and c used in the following equation (1) described below are set to values ​​for traveling in a traffic jam (step S150). In step S110, if vehicle speed V is less than threshold value Vref1, but in steps S120 to S140, vehicle speed V is equal to or greater than threshold value Vref2, rotation speed Ne exceeds threshold value Neref, or load factor KL exceeds threshold value KLref, it is determined that hybrid vehicle 20 is traveling in an urban area, that is, traveling in an urban area, and constants a, b, and c used in equation (1) described below are set to values ​​for traveling in an urban area (step S160). If the vehicle speed V is equal to or greater than the threshold value Vref1 in step S110, it is determined that the hybrid vehicle 20 is traveling at high speed on a highway, and the constants a, b, and c used in equation (1) described later are set to values ​​for high-speed traveling (step S170). In steps S150 to S170, the constants a, b, and c for traveling in traffic jams, traveling in urban areas, and traveling at high speed are set to values ​​previously determined by experiment, analysis, machine learning, etc. for traveling in traffic jams, traveling in urban areas, and traveling at high speed.

[0023] Once the constants a, b, and c are set in this manner, a precursor accumulation rate Vp is calculated as the weight of sludge precursors accumulated in a unit volume of lubricating oil per unit time using the following equation (calculation formula) (1) and the coolant temperature Tw (step S180). Then, using the precursor accumulation rate Vp, the fuel consumption rate Fi as the fuel injection amount per injection by engine 22 (the sum of the fuel injection amount per injection from port injection valve 126 and the fuel injection amount per injection from direct injection valve 127), and the fuel density Df as the weight per unit volume of the fuel (gasoline, diesel, etc.) for engine 22, a precursor accumulation amount Ap is calculated according to the following equation (2) (step S190). Since the precursor accumulation amount Ap is calculated using the constants a, b, and c that are set in accordance with the driving pattern, such as traffic jam driving, urban driving, or highway driving, an appropriate precursor accumulation amount Ap can be calculated in accordance with the driving pattern.

[0024] Vp=a·(b-Tw) 2 +c (1) Ap = Vp Fi Df (2)

[0025] Then, the calculated precursor accumulation amount Ap is added to the precursor accumulation amount Sp (previous Sp) which is the accumulated amount of the precursor accumulation amount Ap calculated the previous time this routine was executed, and the precursor accumulation amount Sp is calculated by the following equation (3) (step S200). The precursor accumulation amount Sp is set to a value of 0 as an initial value when the hybrid vehicle 20 is first used after manufacture, and is reset to a value of 0 every time the lubricating oil is changed.

[0026] Sp=Previous Sp+Ap...(3)

[0027] After calculating the precursor cumulative amount Sp, it is determined whether the precursor cumulative amount Sp is equal to or greater than a threshold (predetermined amount) Spref (step S210). The threshold Spref is a threshold for determining whether or not the lubricating oil needs to be changed, and is a value determined in advance through experiments, analysis, machine learning, etc.

[0028] If the precursor cumulative amount Sp is less than the threshold value Spref in step S210, it is determined that the lubricating oil does not need to be changed, and the routine is terminated. If the precursor cumulative amount Sp is equal to or greater than the threshold value Spref in step S210, it is determined that the lubricating oil needs to be changed, and an oil change signal is sent to the data server 90 or the mobile terminal 92 (step S220), and the routine is terminated. The data server 90, upon receiving the oil change signal, notifies the car dealership staff on a display (not shown) that an oil change is required. This allows the staff at the car dealership to be notified at an appropriate time that an oil change is required, and can encourage the staff to take necessary measures, such as changing the oil, when the hybrid vehicle 20 is brought into a workshop attached to the car dealership. The mobile terminal 92, upon receiving the oil change signal, notifies the car dealership staff on a display (not shown) using an installed application that an oil change is required. This allows the user of the hybrid vehicle 20 to be notified at an appropriate time that an oil change is required, and can encourage the user to change the oil in the hybrid vehicle 20.

[0029] According to the oil change notification system 10 that executes the oil change notification method of the embodiment described above, the current driving pattern is determined based on the vehicle speed V, the engine 22 rotation speed Ne, and the engine 22 load factor KL, and the precursor accumulation amount Ap is calculated based on the above-mentioned formula (1), which differs for each driving pattern, and the fuel consumption amount Fi of the engine 22.When the precursor accumulation amount Sp, which is the accumulation of the calculated precursor accumulation amount Ap, is equal to or greater than the threshold value Spref, the system notifies the driver that the lubricating oil needs to be changed, thereby enabling the driver to be notified at the appropriate time that the lubricating oil needs to be changed.

[0030] The above describes the form for carrying out the present invention using examples, but the present invention is not limited to these examples in any way, and it goes without saying that the present invention can be carried out in various forms within the scope that does not deviate from the gist of the present invention. [Explanation of symbols]

[0031] 10 replacement notification systems, 70 electronic control units (ECUs), 90 servers.

Claims

[Claim 1] An oil change notification method for notifying a vehicle that an oil lubricating an engine mounted on the vehicle needs to be changed, comprising: determining a current driving pattern based on the vehicle speed, the engine rotation speed, and the engine load factor; calculating a precursor accumulation amount as an accumulation amount of sludge precursors accumulated in the oil per unit time based on a calculation formula that differs for each driving pattern and the fuel consumption amount of the engine; When the calculated cumulative amount of the precursor accumulation is equal to or greater than a predetermined amount, a notification is given that the oil needs to be changed. Oil change notification method.

Images