JP2021008924A - Estimation device, estimation method and estimation program - Google Patents

Abstract

To estimate a cumulative damage degree of a bearing part effectively.SOLUTION: An estimation device 100 which estimates a cumulative damage degree of a bearing part 44 to which a lubrication oil is supplied includes: a rotational frequency acquisition part 110 for acquiring the rotational frequency of a rotor 43 pivotally supported by the bearing part 44; an oil-free rotation time acquisition part 120 for acquiring the oil-free rotation time during which the rotor 43 rotates in a state where the lubrication oil to be supplied to the bearing part 44 is deficient or in an oil-free state where the lubrication oil is not supplied; and a cumulative damage degree estimation calculation part 130 for estimating and calculating the cumulative damage degree of the bearing part 44 on the basis of the rotational frequency and the oil-free rotation time to be acquired.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to an estimation device, an estimation method, and an estimation program, and more particularly to a technique relating to life estimation of a bearing portion.

Generally, the lubricating oil supply device of an engine pumps the lubricating oil stored in the oil pan by a pump driven by the power of the engine and pumps it to the oil gallery, and the lubricating oil introduced into the oil gallery is pumped by the valve mechanism and oil. It is configured to supply each lubricating element such as a jet, a journal portion of a crankshaft, and a bearing of a turbocharger (see, for example, Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2014-088820 Japanese Unexamined Patent Publication No. 2008-101568

By the way, when the engine is stopped due to a long-term stop of the vehicle, idling stop, etc., the drive of the pump is also stopped accordingly, so that the lubricating oil may run out from the bearings of the turbocharger or the like. Therefore, for example, when the turbocharger is driven before the lubricating oil is supplied to the bearings of the turbocharger at the time of starting the engine, the bearings support the turbo shaft in a non-lubricated state in which the supply of the lubricating oil is cut off. It will be.

If the turbocharger is repeatedly driven without lubrication, damage is accumulated in the bearing, which may eventually lead to damage to the bearing. Therefore, it is desirable to effectively estimate the cumulative damage degree of the bearing and grasp the life of the bearing in advance.

The technique of the present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to effectively estimate the cumulative damage degree of the bearing portion.

The apparatus of the present disclosure is an estimation device for estimating the cumulative damage degree of a bearing portion to which lubricating oil is supplied, and includes a rotation speed acquisition unit for acquiring the rotation speed of a rotating body pivotally supported by the bearing portion, and the above-mentioned device. The non-lubricating rotation time acquisition unit that acquires the non-lubricating rotation time for the rotating body to rotate when the lubricating oil supplied to the bearing portion is insufficient or the lubricating oil is not supplied, and the acquisition It is characterized by including a cumulative damage degree estimation calculation unit that estimates and calculates the cumulative damage degree of the bearing portion based on the rotation speed and the oil-free rotation time.

Further, it is preferable to further include a warning processing unit that warns when the estimated cumulative damage degree reaches a predetermined threshold value indicating the possibility of damage to the bearing portion.

Further, the lubricating oil is supplied by a pump driven by the power of the engine, and the bearing portion is a bearing that pivotally supports the rotation shaft of the turbocharger driven by the exhaust of the engine and pumps the intake air. The number acquisition unit acquires the number of rotations of the rotating shaft, and the oil-free rotation time acquisition unit acquires the time from the start of the engine to the supply of lubricating oil to the bearing as the oil-free rotation time. Is preferable.

The method of the present disclosure is an estimation method for estimating the cumulative damage degree of a bearing portion to which lubricating oil is supplied, and obtains the number of rotations of a rotating body pivotally supported by the bearing portion and supplies the lubricating oil to the bearing portion. In a non-lubricated state where the bearing oil is insufficient or no lubricating oil is supplied, the non-lubricating rotation time for the rotating body to rotate is acquired, and the acquired rotation speed and the non-lubricating rotation time are obtained. Based on the above, the cumulative damage degree of the bearing portion is estimated and calculated.

In the program of the present disclosure, the computer is operated in a rotation speed acquisition unit that acquires the rotation speed of a rotating body pivotally supported by a bearing portion to which lubricating oil is supplied, and in a non-lubricated state in which lubricating oil is not supplied to the bearing portion. , The oil-free rotation time acquisition unit that acquires the oil-free rotation time during which the rotating body rotates, and the cumulative damage that estimates the cumulative damage degree of the bearing unit based on the acquired rotation speed and the oil-free rotation time. It is characterized by functioning as a degree estimation calculation unit.

According to the technique of the present disclosure, the cumulative damage degree of the bearing portion can be effectively estimated.

It is a schematic overall block diagram which shows the lubricating oil supply device of the engine which concerns on this embodiment. It is a schematic overall block diagram which shows the intake / exhaust system of the engine which concerns on this embodiment. It is a schematic functional block diagram which shows the control device which concerns on this embodiment, and the related peripheral configuration. It is a schematic diagram which shows an example of the SN diagram of the bearing which concerns on this embodiment. It is a flowchart explaining the estimation process of the cumulative damage degree of the bearing which concerns on this embodiment.

Hereinafter, the estimation device, the estimation method, and the estimation program according to the present embodiment will be described with reference to the accompanying drawings. The same parts have the same reference numerals, and their names and functions are also the same. Therefore, detailed explanations about them will not be repeated.

[Lubricating oil supply device]
FIG. 1 is a schematic overall configuration diagram showing a lubricating oil supply device 50 of the engine 10 according to the present embodiment.

As shown in FIG. 1, the lubricating oil supply device 50 supplies lubricating oil to each lubricating element of the engine 10, and includes an oil pan 51, an oil strainer 52, an oil pump 53 (the pump of the present disclosure), and the like. It includes a relief valve 54, an oil filter 55, an oil gallery 60, and pipes 70, 71, 72.

The oil pan 51 is attached to the lower part of the cylinder block CB (crankcase CA) of the engine 10. The oil pan 51 stores lubricating oil.

The oil strainer 52 is immersed in the lubricating oil in the oil pan 51. The oil strainer 52 is a filter that removes foreign substances contained in the lubricating oil. The suction port of the oil pump 53 is connected to the oil strainer 52 via a lubricating oil suction pipe 70.

The oil pump 53 pumps up the lubricating oil in the oil pan 51 and pumps it, and is attached to a side portion of, for example, a cylinder block CB or the like. The oil pump 53 is connected to the crankshaft 10A via a belt, pulley, or the like (not shown), and is driven by the power of the engine 10. A first lubricating oil supply pipe 71 is connected to the discharge port of the oil pump 53.

The relief valve 54 is interposed in a relief pipe 54A that connects the first lubricating oil supply pipe 71 and the lubricating oil suction pipe 70 and bypasses the oil pump 53. The relief valve 54 opens during medium- and high-speed rotation of the engine 10 in which the pumping amount of the oil pump 53 increases so that the oil pressure in the oil gallery 60 does not rise excessively, and the lubricating oil is circulated.

An inlet port of the oil filter 55 is connected to the downstream end of the first lubricating oil supply pipe 71. The oil filter 55 removes foreign matter contained in the lubricating oil pumped from the oil pump 53, and a filter element 55A that functions as a filter medium is housed in the housing thereof. A second lubricating oil supply pipe 72 is connected to the outlet port of the oil filter 55.

An oil gallery 60 is connected to the downstream end of the second lubricating oil supply pipe 72. The lubricating oil introduced into the oil gallery 60 is supplied to each lubricating element such as the valve operating mechanism 11, the oil jet 12, the journal portion of the crankshaft 10A, and the bearing 44 of the turbocharger 40 (an example of the bearing portion of the present disclosure). Lubrication. The lubricating oil that lubricates each lubricating element is returned to the oil pan 51 via a return oil passage (not shown).

[Engine intake / exhaust system]
FIG. 2 is a schematic overall configuration diagram showing an intake / exhaust system of the engine 10 according to the present embodiment.

The engine 10 is provided with an intake manifold 20 that distributes intake air to each cylinder C. Further, the engine 10 is provided with an exhaust manifold 30 for collecting the exhaust gas discharged from each cylinder C. The engine 10 is not limited to the plurality of cylinders in the illustrated example, and may be a single cylinder.

An intake passage 21 for introducing intake air is connected to the intake manifold 20. The intake passage 21 is provided with an air cleaner 22, a turbocharger 40 compressor 42, an intercooler 23, and the like in this order from the intake upstream side.

An exhaust passage 31 that guides exhaust gas to the atmosphere is connected to the exhaust manifold 30. The exhaust passage 31 is provided with a turbine 41 of the turbocharger 40, an exhaust aftertreatment device (not shown), and the like in order from the exhaust upstream side.

The turbocharger 40 includes a turbine 41 that is rotationally driven by exhaust gas, and a compressor 42 that is connected to the turbine 41 via a turbo shaft 43 to pump intake air. The turbo shaft 43, the turbine 41, and the compressor 42 are examples of the rotating bodies of the present disclosure.

The turbo shaft 43 is rotatably supported by a bearing 44 in the housing 45. Lubricating oil is supplied to the bearing 44 from the above-mentioned lubricating oil supply device 50 (see FIG. 1). The turbocharger 40 is not limited to the conventional type shown in the illustrated example, and may be a variable capacitance type having variable wings.

Engine speed sensor 90, from the crankshaft 10A, detects the engine rotational speed NR _E. The accelerator opening sensor 91 detects the accelerator opening AC according to the amount of depression of the accelerator pedal (not shown). The boost pressure sensor 92 is provided in an intake passage 21 (for example, an intake manifold 20) on the upstream side of the compressor 42, and detects the pressure of the intake air pressure-fed by the compressor 42 (hereinafter, boost pressure BP). Turbo rotation speed sensor 93, turbo shaft 43 (or, a compressor 42, etc.) for detecting a turbo revolution speed NR _T from. The oil state amount acquisition sensor 94 is provided in the lubricating oil passage (for example, the second lubricating oil supply pipe 72 of the lubricating oil supply device 50 shown in FIG. 1) on the upstream side of the bearing 44, and the hydraulic pressure of the lubricating oil Or detect the oil flow rate. The intake air flow rate sensor 95 is provided in the intake passage 21 immediately downstream of the air cleaner 22 and detects the intake air flow rate MAF. The sensor values of each of these sensors 90 to 95 are transmitted to the electrically connected control device 100.

[Control device]
FIG. 3 is a schematic functional block diagram showing the control device 100 according to the present embodiment and related peripheral configurations.

The control device 100 is, for example, a device that performs calculations such as a computer, and is a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an input port, and an output port connected to each other by a bus or the like. Etc., and execute the estimation program.

Further, the control device 100 functions as a device including a turbo rotation speed acquisition unit 110, a refueling-free rotation time acquisition unit 120, a cumulative damage degree estimation calculation unit 130, and a warning processing unit 140 by executing an estimation program. Each of these functional elements will be described as being included in the control device 100, which is integrated hardware in the present embodiment, but any part of these may be provided in separate hardware.

Turbo rotation speed acquisition unit 110 acquires the turbo rotational speed NR _T sent from the turbo rotation speed sensor 93. Turbo speed NR _T obtained by the turbo speed acquisition unit 110 is sent to the cumulative damage degree estimation calculation section 130. Note that the turbo rotation speed NR _T is and boost pressure BP transmitted from the boost pressure sensor 92, based on the intake air flow rate MAF or the like transmitted from the intake air flow rate sensor 95, by estimation calculation from the model equation or a map You may get it.

The oil-free rotation time acquisition unit 120 is the time from the start of the engine 10 (start of driving the oil pump 53) to the supply of lubricating oil to the bearing 44 of the turbocharger 40, in other words, the lubricating oil supplied to the bearing 44. The control device 100 determines the time during which the turbocharger 40 is driven (hereinafter, simply referred to as the non-lubricated rotation time t _NO ) in a state where the bearings are interrupted or insufficient (hereinafter, these are also referred to as a non-lubricated state). Obtained by measuring with a built-in timer (not shown).

The engine 10 may be started by switching the ignition switch 98 from OFF to ON, or when the engine 10 has an idling stop function, it may be acquired based on the satisfaction of the idling stop release condition. Further, in the non-lubricated state in which the lubricating oil supplied to the bearing 44 is insufficient or the lubricating oil is not supplied, the sensor value is a predetermined threshold value based on the sensor value (hydraulic or oil flow rate) of the oil state amount acquisition sensor 94. In the following cases, it may be determined that there is no refueling. The non-lubricated rotation time t _NO acquired by the non-lubricated rotation time acquisition unit 120 is transmitted to the cumulative damage degree estimation calculation unit 130.

The oil-free rotation time t _NO is obtained by storing a map in the memory of the control device 100 that defines the relationship between the drive rotation speed of the oil pump 53 and the time until the lubricating oil reaches the bearing 44. The map may be obtained by referring to the driving speed of the oil pump 53. Driving rotation speed of the oil pump 53 may be obtained based on the engine speed NR _E sent from the engine speed sensor 90.

Cumulative damage degree estimation calculation section 130, and the oil-free rotation time t _NO, on the basis of the turbo rotation speed NR _T in the oil-free rotation time t _NO, the cumulative damage of D _T of the bearing 44 according to Miner's law or modified Miner's law Is calculated.

Specifically, in the memory of the control device 100, an SN diagram G (see FIG. 4 for details) that defines the fatigue fracture limit of the bearing 44 created in advance by experiments or the like is stored. In the SN diagram G, the horizontal axis shows the turbo rotation speed NR _{T_i} , and the vertical axis _shows the limit oil-free rotation time T _{NO_i} corresponding to the cumulative time until damage occurs when the bearing 44 rotates in the oil-free state. It is set.

The cumulative damage degree estimation calculation unit 130 has a turbo rotation speed NR _{T_i} transmitted from the turbo rotation speed acquisition unit 110 and a no- _fuel rotation speed t _{NO_i} transmitted from the oil-free rotation time acquisition unit 120 (turbo rotation speed NR at a certain moment). _Based on the time measured according to _{T_i} ) and the limit oil-free rotation time T _{NO_i} read from the SN diagram G, the cumulative damage degree _DT of the bearing 44 is calculated from the following mathematical formula (1).

警告処理部１４０は、累積被害度推定演算部１３０によって算出されるベアリング４４の累積被害度Ｄ_Ｔが破損時期（Ｄ_Ｔ＝１）に近い所定の破損閾値（例えば、０．９等）に達すると、運転室内の表示器２００にベアリング４４の交換が必要な旨（又は、破損の可能性がある旨）を表示させる指示信号を送信する。なお、警告の手法は表示器２００への表示に限定されず、図示しないスピーカ等による音声によって行ってもよい。また、ベアリング４４の交換が必要な旨は、車両の運転者のみならず、通信装置（不図示）を介して、車両の運行管理基地局や整備工場等に送信してもよい。

In the warning processing unit 140, the cumulative damage degree _DT of the bearing 44 calculated by the cumulative damage degree estimation calculation unit 130 reaches a predetermined damage threshold value (for example, 0.9, etc.) close to the damage time ( _DT = 1). Then, an instruction signal is transmitted to the display 200 in the driver's cab to indicate that the bearing 44 needs to be replaced (or that there is a possibility of damage). The warning method is not limited to the display on the display 200, and may be performed by voice from a speaker or the like (not shown). Further, the fact that the bearing 44 needs to be replaced may be transmitted not only to the driver of the vehicle but also to the operation management base station of the vehicle, the maintenance shop, etc. via a communication device (not shown).

Next, the flow of the estimation process of the cumulative damage degree _DT of the bearing 44 according to the present embodiment will be described with reference to FIG.

In step S100, it is determined whether or not the engine 10 has started. Whether or not the engine 10 has started may be determined based on the ON operation of the ignition switch 98 or, if it has the idling stop function, the satisfaction of the idling stop release condition. When the engine 10 is started (Yes), this control proceeds to the process of step S110. On the other hand, when the engine 10 is not started (No), this control is returned.

In step S110, it is determined whether or not the turbocharger 40 is in a non-lubricated state. Whether or not it is in the non-lubricated state may be determined based on the sensor value of the oil state amount acquisition sensor 94. When the turbocharger 40 is in the non-lubricated state (Yes), this control proceeds to the process of S120. On the other hand, when the turbocharger 40 is not in the non-lubricated state (No), that is, when the stop period of the engine 10 is short and the lubricating oil remains in the bearing 44, this control is returned.

In step S120, the control unit 100 built-in timer and starts counting the oilless rotation time _{t NO,} acquires the turbo rotational speed _{NR T_i} of the turbocharger 40.

Next, in step S130, it is determined whether or not the lubricating oil has reached the bearing 44 of the turbocharger 40. If the oil pressure or oil flow rate acquired by the oil state amount acquisition sensor 94 exceeds a predetermined threshold value, it is determined that the lubricating oil has reached the bearing 44, and this control proceeds to the process of step S140 (Yes). On the other hand, when the oil pressure or the oil flow rate acquired by the oil state amount acquisition sensor 94 is equal to or less than a predetermined threshold value (No), this control repeats the process of step S120 until the lubricating oil reaches the bearing 44. ..

In step S140, the bearing 44 is _derived from the above equation (1) based on the turbo rotation speed NR _{T_i} , the oil-free rotation time t _{NO_i,} and the limit oil-free rotation time T _{NO_i} read from the SN diagram G (see FIG. 4). Calculate the cumulative damage degree _DT of.

Next, in step S150, it is determined whether or not the cumulative damage degree _DT of the bearing 44 has reached a predetermined breakage threshold value (for example, 0.9 or the like) close to the breakage time ( _DT = 1). When the cumulative damage degree _DT reaches the damage threshold value (Yes), this control proceeds to the process of step S160. On the other hand, when the cumulative damage degree _DT has not reached the damage threshold value (No), this control is returned to the process of step S100.

In step S160, a warning is executed to indicate to the display 200 in the driver's cab that the bearing 44 of the turbocharger 40 needs to be replaced or that the bearing 44 may be damaged, and then this control ends. To do.

According to the embodiment described above, the turbo and the turbo rotational speed NR _T turbo shaft 43, without lubrication state or lubricating oil supplied to the bearing 44 is insufficient, or the lubricating oil is not supplied axis 43 is based on the oil-free rotation time t _NO rotating, together effectively estimate the cumulative damage of D _T of the bearing 44, the cumulative damage of D _T reaches a predetermined damage threshold, a warning appropriately It is configured to do. As a result, the life of the bearing 44 and the replacement time of the bearing 44 can be effectively grasped before the bearing 44 is damaged, and it is possible to prevent the turbocharger 40 from failing. .. Further, by grasping the life of the bearing 44 in advance, it becomes possible to perform maintenance of the vehicle at an appropriate timing, and it is possible to improve the operation management of the vehicle.

[Other]
It should be noted that the present disclosure is not limited to the above-described embodiment, and can be appropriately modified and implemented without departing from the spirit of the present disclosure.

For example, the application of the above embodiment is not limited to the bearing 44 of the turbocharger 40, and if it is a bearing portion to which lubricating oil is supplied from the oil pump 53, for example, a bearing that pivotally supports the camshaft of the valve operating mechanism 11. It is also possible to apply it to other bearings.

Further, the application of the above embodiment is not limited to the start of the engine 10, and if the lubricating oil of the bearing portion is insufficient or the supply of the lubricating oil is interrupted in a non-lubricated state, other than the start time. It may be configured to include operating conditions.

10 Engine 40 Turbocharger 41 Turbine (rotating body)
42 Compressor (rotating body)
43 Turbo shaft (rotating body)
44 Bearing (bearing part)
50 Lubricating oil supply device 51 Oil pan 52 Oil strainer 53 Oil pump (pump)
55 Oil filter 60 Oil gallery 70,71,72 Piping 90 Engine speed sensor 91 Accelerator opening sensor 92 Boost pressure sensor 93 Turbo speed sensor 94 Oil condition acquisition sensor 95 Intake air flow sensor 100 Control device 110 Turbo speed Acquisition unit 120 Oil-free rotation time acquisition unit 130 Cumulative damage estimation calculation unit 140 Warning processing unit

Claims (5)

It is an estimation device that estimates the cumulative damage level of the bearing part to which lubricating oil is supplied.
A rotation speed acquisition unit that acquires the rotation speed of a rotating body pivotally supported by the bearing unit, and a rotation speed acquisition unit.
A non-lubricated rotation time acquisition unit that acquires a non-lubricated rotation time for rotating the rotating body in a non-lubricated state in which the lubricating oil supplied to the bearing portion is insufficient or no lubricating oil is supplied.
An estimation device including a cumulative damage degree estimation calculation unit that estimates and calculates the cumulative damage degree of the bearing portion based on the acquired rotation speed and the oil-free rotation time. The estimation device according to claim 1, further comprising a warning processing unit that warns when the estimated cumulative damage degree reaches a predetermined threshold value indicating the possibility of damage to the bearing portion. The lubricating oil is supplied by a pump driven by the power of the engine.
The bearing portion is a bearing that pivotally supports the rotation shaft of the turbocharger that is driven by the exhaust of the engine and pumps the intake air.
The rotation speed acquisition unit acquires the rotation speed of the rotation shaft and obtains the rotation speed.
The estimation device according to claim 1 or 2, wherein the non-lubricating rotation time acquisition unit acquires the time from the start of the engine until the lubricating oil is supplied to the bearing as the non-lubricating rotation time. This is an estimation method for estimating the cumulative damage level of bearings to which lubricating oil is supplied.
The number of rotations of the rotating body pivotally supported by the bearing portion is acquired, and the rotating body is in a non-lubricated state in which the lubricating oil supplied to the bearing portion is insufficient or the lubricating oil is not supplied. An estimation method characterized in that the cumulative damage degree of the bearing portion is estimated and calculated based on the acquired rotation speed and the oil-free rotation time. Engine computer,
Rotation speed acquisition unit, which acquires the rotation speed of the rotating body pivotally supported by the bearing unit to which the lubricating oil is supplied.
A non-lubricated rotation time acquisition unit that acquires a non-lubricated rotation time for rotating the rotating body in a non-lubricated state in which the lubricating oil supplied to the bearing portion is insufficient or no lubricating oil is supplied.
An estimation program characterized in that it functions as a cumulative damage degree estimation calculation unit that estimates the cumulative damage degree of the bearing portion based on the acquired rotation speed and the oil-free rotation time.

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