WO2020189638A1

WO2020189638A1 - Engine oil quantity estimating device, and engine oil quantity estimating method

Info

Publication number: WO2020189638A1
Application number: PCT/JP2020/011523
Authority: WO
Inventors: 伸白尾; 直人村澤
Original assignee: いすゞ自動車株式会社
Priority date: 2019-03-20
Filing date: 2020-03-16
Publication date: 2020-09-24
Also published as: JP2020153319A

Abstract

Provided are an engine oil quantity estimating device and an engine oil quantity estimating method capable of accurately estimating a quantity of engine oil. This engine oil quantity estimating device is provided with: a temperature acquiring unit for acquiring the temperature of engine oil collected in an oil pan of an internal combustion engine; a calculating unit for calculating the rate of decrease in the temperature after the internal combustion engine has stopped, on the basis of the acquired temperature of the engine oil; and an estimating unit for estimating the quantity of engine oil on the basis of the calculated rate of decrease in temperature. The engine oil quantity estimating method includes: acquiring the temperature of engine oil collected in an oil pan of an internal combustion engine; calculating the rate of decrease in the temperature after the internal combustion engine has stopped, on the basis of the acquired temperature of the engine oil; and estimating the quantity of engine oil on the basis of the calculated rate of decrease in temperature.

Description

Engine oil amount estimation device and engine oil amount estimation method

The present disclosure relates to an engine oil amount estimation device and an engine oil amount estimation method.

The lubricating oil supply device of an internal combustion engine (for example, a diesel engine) pumps the engine oil (lubricating oil) stored in the oil pan by an oil pump and pumps it to the oil gallery, and the engine oil introduced into the oil gallery is rubbed. It is configured to supply to a moving element (for example, a valve operating mechanism, an oil jet, a journal portion of a crank shaft, a rotating shaft of a turbocharger, etc.) (see, for example, Patent Documents 1 and 2).

Since the engine oil is discharged to the outside of the vehicle together with the exhaust gas, the amount (remaining amount) of the engine oil will gradually decrease. When the amount of engine oil decreases, it becomes impossible to lubricate each sliding element with engine oil. Therefore, when the engine oil is low, the engine oil is replaced. In addition, the post-injection performed to burn the soot accumulated in the DPF (Diesel Particulate Filter) promotes the dilution of the engine oil by the fuel, and the engine oil is replaced even when the engine oil increases.

Patent Document 3 discloses a technique for estimating the amount of engine oil in order to determine whether the amount of engine oil is decreasing. In the technique described in Patent Document 3, the rising speed of the oil temperature is derived based on the measurement result of the oil temperature measuring means during the warm-up operation of the engine, and the amount of engine oil is estimated from the derived rising speed of the oil temperature. are doing.

Japanese Patent Application Laid-Open No. 2014-08820 Japanese Patent Application Laid-Open No. 2008-101568 Japanese Patent Application Laid-Open No. 2008-223632

However, in the technique described in Patent Document 3, the amount of heat generated by the internal combustion engine differs depending on the difference in operating conditions (for example, engine speed) during warm-up operation, and the rate of increase in oil temperature varies widely. There was a problem that the amount of oil could not be estimated accurately.

An object of the present disclosure is to provide an engine oil amount estimation device and an engine oil amount estimation method capable of accurately estimating the amount of engine oil.

The engine oil amount estimation device according to the present disclosure is
A temperature acquisition unit that acquires the temperature of engine oil stored in the oil pan of an internal combustion engine,
Based on the acquired temperature of the engine oil, a calculation unit that calculates the rate of decrease in the temperature after the internal combustion engine is stopped, and a calculation unit.
An estimation unit that estimates the amount of engine oil based on the calculated rate of decrease in temperature,
To be equipped.

The engine oil amount estimation method according to the present disclosure is
Obtain the temperature of the engine oil stored in the oil pan of the internal combustion engine,
Based on the acquired temperature of the engine oil, the rate of decrease of the temperature after the internal combustion engine is stopped is calculated.
The amount of the engine oil is estimated based on the calculated rate of decrease in the temperature.

According to the present disclosure, the amount of engine oil can be estimated accurately.

FIG. 1 is a diagram showing a configuration of a lubricating oil supply device according to the present embodiment. FIG. 2 is a diagram showing a configuration of a control device according to the present embodiment. FIG. 3 is a diagram illustrating a decrease in engine oil after the internal combustion engine is stopped. FIG. 4 is a flowchart showing an example of the engine oil amount estimation process in the present embodiment. FIG. 5 is a diagram illustrating a modified example of the engine oil amount estimation process in the present embodiment. FIG. 6 is a diagram illustrating a modified example of the engine oil amount estimation process in the present embodiment.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. FIG. 1 is a diagram showing a configuration of a lubricating oil supply device 100 according to the present embodiment.

As shown in FIG. 1, the lubricating oil supply device 100 is mounted on a vehicle (not shown), and engine oil (lubricating oil) is applied to each sliding element in the internal combustion engine 10 (for example, a diesel engine) and the turbocharger 40. It is a device to supply.

The lubricating oil supply device 100 includes an oil pan 111, an oil strainer 112, an oil pump 113, a relief valve 114, an oil filter 115, an oil gallery 130, pipes 120 to 122, and a control device 200. I have.

The oil pan 111 stores engine oil and is attached to the lower part of the cylinder block (not shown) of the internal combustion engine 10. The oil strainer 112 is a filter that is immersed in the engine oil in the oil pan 111 to remove foreign substances contained in the engine oil.

A temperature detection unit 140 is provided in the oil pan 111. The temperature detection unit 140 detects the temperature of the engine oil stored in the oil pan 111, and outputs a signal corresponding to the temperature to the control device 200.

The oil strainer 112 is connected to the suction port of the oil pump 113 via the engine oil suction pipe 120.

The oil pump 113 is attached to a side portion of the internal combustion engine 10 such as a cylinder block (not shown), and pumps up and pumps engine oil in the oil pan 111.

The oil pump 113 is connected to the crankshaft 10A via a gear or the like (not shown), and is driven by the power of the internal combustion engine 10. A first engine oil supply pipe 121 is connected to the discharge port of the oil pump 113.

The relief valve 114 is interposed in a relief pipe 114A that connects the first engine oil supply pipe 121 and the engine oil suction pipe 120 and bypasses the oil pump 113. The relief valve 114 is opened at the time of medium and high speed rotation of the internal combustion engine 10 in which the pumping amount of the oil pump 113 increases so that the hydraulic pressure in the oil gallery 130 does not rise excessively, and the engine oil is circulated.

The inlet port of the oil filter 115 is connected to the downstream end of the first engine oil supply pipe 121.

The oil filter 115 removes foreign matter contained in the engine oil pumped from the oil pump 113. A filter element 115A that functions as a filter medium is housed in the housing of the oil filter 115. A second engine oil supply pipe 122 is connected to the outlet port of the oil filter 115.

An oil gallery 130 is connected to the downstream end of the second engine oil supply pipe 122. The engine oil introduced into the oil gallery 130 is supplied to each sliding element such as the valve operating mechanism 131, the oil jet 132, the journal portion of the crankshaft 10A, and the bearing portion (not shown) of the turbocharger 40. After lubricating the sliding element, it is returned to the oil pan 111.

The control device 200 is, for example, an ECM (Engine Control Module) that controls the internal combustion engine 10 and the lubricating oil supply device 100. The control device 200 functions as the "engine oil amount estimation device" of the present disclosure.

The control device 200 includes a CPU (Central Processing Unit), a ROM (Read Only Memory) in which a control program is stored, and a working memory such as a RAM (Random Access Memory). The CPU reads a control program from the ROM, expands it into the RAM, and controls the execution of various processes in cooperation with the expanded control program.

FIG. 2 is a diagram showing the configuration of the control device 200 according to the present embodiment. As shown in FIG. 2, the control device 200 includes a temperature acquisition unit 210, a stop determination unit 220, a calculation unit 230, a relationship information storage unit 240, and an estimation unit 250.

The temperature acquisition unit 210 inputs the signal output from the temperature detection unit 140 and acquires the temperature of the engine oil stored in the oil pan 111. Then, the temperature acquisition unit 210 sequentially outputs the temperature of the engine oil acquired sequentially to the calculation unit 230.

The stop determination unit 220 determines whether or not the internal combustion engine 10 has stopped. When the stop determination unit 220 determines that the internal combustion engine 10 has stopped, the stop determination unit 220 notifies the calculation unit 230 to that effect. Specifically, when the ignition key (not shown) is turned off, the stop determination unit 220 determines that the internal combustion engine 10 has stopped. On the other hand, when the ignition key is turned ON, the stop determination unit 220 determines that the internal combustion engine 10 has started operation.

The calculation unit 230 calculates the rate of decrease in the temperature of the engine oil after the internal combustion engine 10 is stopped, based on the output from the temperature acquisition unit 210 and the notification from the stop determination unit 220. In the present embodiment, the calculation unit 230 calculates the rate of decrease in the temperature of the engine oil immediately after the internal combustion engine 10 is stopped. Then, the calculation unit 230 outputs the calculated rate of decrease in the temperature of the engine oil to the estimation unit 250.

FIG. 3 is a diagram illustrating a decrease in engine oil after the internal combustion engine 10 is stopped. In FIG. 3, the curve L represents the change in the temperature of the engine oil after the internal combustion engine 10 is stopped.

The calculation unit 230 determines the amount of decrease in the temperature of the engine oil (time T1 in the example of FIG. 3) to the elapse of a predetermined time (time T2 in the example of FIG. 3) immediately after the internal combustion engine 10 is stopped. In the example of FIG. 3, t1-t2) is obtained, and the rate of decrease in the temperature of the engine oil is calculated by dividing the amount of decrease in the temperature of the engine oil by a predetermined time.

The relationship information storage unit 240 stores the relationship information (map information) that defines the relationship between the rate of decrease in the temperature of the engine oil stored in the oil pan 111 and the amount of the engine oil.

The relationship specified in the relationship information is that the rate of decrease in the temperature of the engine oil decreases (that is, it is difficult to cool) in proportion to the increase in the amount of engine oil. This is because the heat capacity of the engine oil changes according to the amount of the engine oil, and the rate of decrease in the temperature of the engine oil differs.

For example, when the amount of engine oil is large, the engine oil is difficult to cool and the rate of decrease in the temperature of the engine oil is small. On the other hand, when the amount of engine oil is small, the engine oil is easily cooled and the temperature of the engine oil decreases at a high rate.

The related information is determined based on experiments and simulations conducted in advance. Further, the related information may be stored in a storage device (not shown) or the like outside the control device 200.

The estimation unit 250 estimates the amount of engine oil based on the rate of decrease in the temperature of the engine oil calculated by the calculation unit 230. In the present embodiment, the estimation unit 250 refers to the relationship information stored in the relationship information storage unit 240, and obtains the amount of engine oil corresponding to the rate of decrease in the temperature of the engine oil output from the calculation unit 230. Estimates the amount of engine oil.

Next, the engine oil amount estimation process of the control device 200 in the present embodiment will be described. FIG. 4 is a flowchart showing the engine oil amount estimation process of the control device 200 according to the present embodiment. The process in FIG. 4 is executed at predetermined time intervals during the operation of the internal combustion engine 10.

First, the stop determination unit 220 determines whether or not the internal combustion engine 10 has stopped (step S100). As a result of the determination, when the internal combustion engine 10 is not stopped (step S100, NO), the control device 200 ends the engine oil amount estimation process in FIG.

On the other hand, when the internal combustion engine 10 is stopped (step S100, YES), the calculation unit 230 uses the engine oil immediately after the internal combustion engine 10 is stopped based on the output from the temperature acquisition unit 210 and the notification from the stop determination unit 220. The rate of decrease in temperature of (step S120) is calculated.

Finally, the estimation unit 250 refers to the relationship information stored in the relationship information storage unit 240, and obtains the amount of engine oil corresponding to the rate of decrease in the temperature of the engine oil output from the calculation unit 230. The amount of oil is estimated (step S140). When the process of step S140 is completed, the control device 200 ends the engine oil amount estimation process in FIG.

As described in detail above, in the present embodiment, the control device 200 (engine oil amount estimation device) is the temperature acquisition unit 210 for acquiring the temperature of the engine oil stored in the oil pan 111 of the internal combustion engine 10 and the acquisition unit 210. A calculation unit 230 that calculates the rate of temperature decrease after the internal combustion engine 10 is stopped based on the calculated engine oil temperature, and an estimation unit that estimates the amount of engine oil based on the calculated temperature decrease rate. It is equipped with 250.

According to the present embodiment configured in this way, after the internal combustion engine 10 is stopped, that is, when the operating conditions of the internal combustion engine 10 are constant (stopped state), the calorific value of the internal combustion engine 10 becomes the same (0), and the engine oil The rate of decrease in the temperature of the engine oil is calculated in a situation where the variation in the temperature change is small, and the amount of the engine oil is estimated based on the calculated rate of decrease in the temperature. Therefore, the amount of engine oil can be estimated more accurately than the conventional technique of estimating the amount of engine oil from the rate of increase in oil temperature during warm-up operation of the engine. Further, since the amount of engine oil can be estimated every time the internal combustion engine 10 is stopped, that is, every driving cycle, when the engine oil is decreasing, the decrease is quickly detected and the engine oil is promptly detected. Can be exchanged.

In the above embodiment, the calculation unit 230 has described an example of calculating the rate of decrease in the temperature of the engine oil immediately after the internal combustion engine 10 is stopped, but the present disclosure is not limited to this. For example, from the viewpoint of more accurately calculating the rate of decrease in the temperature of the engine oil, the calculation unit 230 determines that the engine oil that lubricates the sliding element is substantially oil after the internal combustion engine 10 has stopped and a predetermined time has elapsed (for example, the engine oil that lubricates the sliding element is substantially oil. After returning to the pan 111, the rate of decrease in the temperature of the engine oil in the situation where the variation in the temperature change of the engine oil becomes smaller) may be calculated.

Further, in the above embodiment, the estimation unit 250 has described an example of estimating the amount of engine oil by referring to the relational information stored in the relational information storage unit 240, but the present disclosure is not limited to this. For example, the estimation unit 250 uses an arithmetic formula that defines the relationship between the rate of decrease in the temperature of the engine oil stored in the oil pan 111 and the amount of the engine oil, and the estimation unit 250 determines the amount of engine oil. You may estimate.

Further, in the above embodiment, from the viewpoint of estimating the amount of engine oil more accurately, the estimation unit 250 uses the calculated engine oil temperature decrease rate and parameters that affect the engine oil temperature decrease rate. The amount of engine oil may be estimated based on the values (for example, the cooling water temperature of the internal combustion engine 10, the outside temperature (atmospheric temperature), the outside pressure, the viscosity of the engine oil, the dilution rate of the engine oil, etc.). For example, the estimation unit 250 estimates the amount of engine oil based on the calculated rate of decrease in engine oil temperature, and then sets the estimated amount of engine oil to the outside air temperature (parameter) and the reference temperature (for example, 25). It may be corrected according to the difference from ℃). When the outside air temperature (parameter) is higher than the reference temperature, the estimation unit 250 estimates that the engine oil temperature decreases at a lower rate and the amount of engine oil is larger than when the outside air temperature is the reference temperature. Correct to reduce the estimated amount of engine oil. On the other hand, when the outside air temperature (parameter) is lower than the reference temperature, the estimation unit 250 estimates that the engine oil temperature decreases faster and the amount of engine oil is smaller than when the outside air temperature is the reference temperature. Therefore, it is corrected to increase the estimated amount of engine oil.

Further, the estimation unit 250 corrects the calculated engine oil temperature decrease rate according to the difference between the outside air temperature (parameter) and the reference temperature (for example, 25 ° C.), and then based on the corrected decrease rate. You may estimate the amount of engine oil.

Further, as shown in FIG. 5, the estimation unit 250 refers to the related information 300, and a predetermined time elapses immediately after the internal combustion engine 10 is stopped (time T1 in the example of FIG. 3) (in the example of FIG. 3). , After estimating the amount of engine oil based on the amount of decrease in the temperature of the engine oil up to the time T2) (t1-t2 in the example of FIG. 3), it was estimated by referring to the

related information

310 and 320. The amount of engine oil may be corrected by a correction amount according to the difference between the outside air temperature and the reference temperature and a correction amount according to the difference between the predetermined time and the reference time.

The relationship information 300 defines the relationship between the amount of decrease in the temperature of the engine oil stored in the oil pan 111 and the amount of the engine oil. The relationship defined in the relationship information 300 is a relationship in which the amount of decrease in temperature of the engine oil decreases (that is, it is difficult to cool) in proportion to the increase in the amount of engine oil.

The relationship information 310 defines the relationship between the correction amount of the amount of engine oil stored in the oil pan 111 and the outside air temperature. In the estimation unit 250, when the outside air temperature (parameter) is higher than the reference temperature, the amount of decrease in the temperature of the engine oil is smaller (that is, it is difficult to cool) than when the outside air temperature is the reference temperature. Since it is estimated to be high, it is corrected (to the minus side) to reduce the estimated amount of engine oil. On the other hand, in the estimation unit 250, when the outside air temperature (parameter) is lower than the reference temperature, the amount of decrease in the temperature of the engine oil becomes larger (that is, it is easy to cool) than when the outside air temperature is the reference temperature. Since the amount is estimated to be small, it is corrected (to the plus side) to increase the estimated amount of engine oil.

The relationship information 320 defines the relationship between the correction amount of the amount of engine oil stored in the oil pan 111 and the predetermined time. In the estimation unit 250, when the predetermined time (parameter) is longer than the reference time, the amount of decrease in the temperature of the engine oil becomes larger (that is, it is easy to cool) than when the predetermined time is the reference time, and the amount of the engine oil increases. Since it is underestimated, it is corrected (to the plus side) to increase the estimated amount of engine oil. On the other hand, in the estimation unit 250, when the predetermined time (parameter) is shorter than the reference time, the amount of decrease in the temperature of the engine oil is smaller (that is, it is difficult to cool) than when the predetermined time is the reference time. Since the amount is estimated to be large, it is corrected (to the minus side) to reduce the estimated amount of engine oil.

Further, as shown in FIG. 6, the estimation unit 250 refers to the

related information

400 and 410, and excludes the amount of decrease in the temperature of the engine oil from immediately after the internal combustion engine 10 is stopped until a predetermined time elapses. After correcting with the correction amount according to the difference between the air temperature and the reference temperature and the correction amount according to the difference between the predetermined time and the reference time, refer to the related information 420 and engine oil based on the corrected amount of decrease. You may estimate the amount of.

The relationship information 400 defines the relationship between the correction amount of the temperature drop of the engine oil stored in the oil pan 111 and the outside air temperature. The estimation unit 250 was calculated because when the outside air temperature (parameter) is higher than the reference temperature, the amount of decrease in the temperature of the engine oil is smaller (that is, it is difficult to cool) than when the outside air temperature is the reference temperature. Correct (to the plus side) so that the amount of temperature decrease of the engine oil becomes large. On the other hand, the estimation unit 250 is calculated because when the outside air temperature (parameter) is lower than the reference temperature, the amount of decrease in the temperature of the engine oil becomes larger (that is, it is easier to cool) than when the outside air temperature is the reference temperature. Correct (to the minus side) to reduce the amount of temperature decrease of the engine oil.

The relationship information 410 defines the relationship between the amount of temperature decrease of the engine oil stored in the oil pan 111 and the predetermined time. When the predetermined time (parameter) is longer than the reference time, the estimation unit 250 increases the temperature decrease of the engine oil (that is, it is easy to cool) as compared with the case where the predetermined time is the reference time, so that the calculated engine Correct (to the minus side) to reduce the amount of oil temperature drop. On the other hand, the estimation unit 250 is calculated because when the predetermined time (parameter) is shorter than the reference time, the amount of temperature decrease of the engine oil is smaller (that is, it is difficult to cool) than when the predetermined time is the reference time. Correct (to the plus side) to increase the amount of temperature decrease of the engine oil.

The relationship information 420 defines the relationship between the amount of decrease in the temperature of the engine oil stored in the oil pan 111 and the amount of the engine oil. The relationship defined in the relationship information 420 is a relationship in which the amount of decrease in temperature of the engine oil decreases (that is, it is difficult to cool) in proportion to the increase in the amount of engine oil.

Further, all of the above-described embodiments are merely examples of concrete implementation in carrying out the present disclosure, and the technical scope of the present disclosure should not be construed in a limited manner by these. That is, the present disclosure can be implemented in various forms without departing from its gist or its main features.

This application is based on a Japanese patent application (Japanese Patent Application No. 2019-053675) filed on March 20, 2019, the contents of which are incorporated herein by reference.

The present disclosure is useful as an engine oil amount estimation device and an engine oil amount estimation method capable of accurately estimating the amount of engine oil.

10 Internal engine 10A Crank shaft 40 Turbocharger 100 Lubricating oil supply device 111 Oil pan 112 Oil strainer 113 Oil pump 114 Relief valve 114A Relief piping 115 Oil filter 115A Filter element 120 Engine oil suction piping 121 1st engine oil supply piping 122 2nd Engine oil supply piping 130 Oil gallery 131 Valve mechanism 132 Oil jet 140 Temperature detection unit 200 Control device 210 Temperature acquisition unit 220 Stop judgment unit 230 Calculation unit 240 Related information storage unit 250 Estimator unit

Claims

A temperature acquisition unit that acquires the temperature of engine oil stored in the oil pan of an internal combustion engine,
Based on the acquired temperature of the engine oil, a calculation unit that calculates the rate of decrease in the temperature after the internal combustion engine is stopped, and a calculation unit.
An estimation unit that estimates the amount of engine oil based on the calculated rate of decrease in temperature,
An engine oil amount estimation device equipped with.
The calculation unit calculates the rate of decrease in temperature immediately after the internal combustion engine is stopped.
The engine oil amount estimation device according to claim 1.
The calculation unit calculates the rate of decrease in temperature after the internal combustion engine has stopped and a predetermined time has elapsed.
The engine oil amount estimation device according to claim 1.
The estimation unit estimates the amount of engine oil stored in the oil pan with reference to the relationship information that defines the relationship between the rate of decrease in the temperature of the engine oil and the amount of the engine oil.
The engine oil amount estimation device according to claim 1.
The estimation unit estimates the amount of the engine oil based on the calculated rate of decrease in temperature and the value of a parameter that affects the rate of decrease in temperature of the engine oil.
The engine oil amount estimation device according to claim 1.
Obtain the temperature of the engine oil stored in the oil pan of the internal combustion engine,
Based on the acquired temperature of the engine oil, the rate of decrease of the temperature after the internal combustion engine is stopped is calculated.
The amount of the engine oil is estimated based on the calculated rate of decrease in the temperature.
Engine oil amount estimation method.