JP6504076B2 - Oil supply device - Google Patents

Description

  The present invention relates to an oil supply device provided with an electric oil pump.

  DESCRIPTION OF RELATED ART Conventionally, the supply apparatus which supplies the engine with the oil currently stored by the oil pan through a supply path is known by using an electrically-driven oil pump (for example, patent document 1).

JP 2007-2682 A

  By the way, when the oil contains water, the water may freeze in the supply path during the cold engine stop. If the water freezes in the supply path, it may cause clogging of the supply path.

  An object of the present invention is to provide an oil supply device capable of suppressing clogging of the oil supply path due to freezing of water in the oil supply path.

  An oil supply device for solving the above problems includes an oil pan for storing oil, and an electric oil pump connected to a supply path for supplying oil to an engine and delivering oil pumped out of the oil pan to the supply path; The oil supply device has a control unit that controls the drive of the electric oil pump, and includes an estimation unit that estimates the amount of water in the oil, and the control unit is configured to calculate the estimated amount of water as a predetermined threshold. The electric oil pump is reversely driven so that oil is discharged from the supply path to the oil pan for a predetermined period of time from when the operation of the engine is stopped, on condition that the pressure is exceeded.

  If the amount of water in the oil exceeds a predetermined threshold value, the water may freeze in the oil supply path and clogging of the supply path may occur. Here, immediately after the operation of the engine is stopped, the oil supply path is filled with oil, but as time passes after the operation of the engine is stopped, the oil is naturally discharged from the supply path, Air bubbles may be mixed in the oil supply path. Even when the electric oil pump is driven so that the oil is discharged from the supply passage to the oil pan in a state where air bubbles are mixed in the oil supply passage, it is difficult to efficiently discharge the oil from the supply passage. In the present invention, oil can be efficiently discharged from the oil supply path by reversely driving the electric oil pump for a predetermined period of time after the operation of the engine is stopped. Therefore, it is possible to suppress clogging of the supply path of the oil due to freezing of the water in the supply path of the oil.

The schematic diagram of an oil supply apparatus. The flowchart which shows the process which estimates the water content in oil. The flowchart which shows the processing which drives an electric oil pump.

Hereinafter, an embodiment of the oil supply device will be described.
As shown in FIG. 1, the oil supply device of this embodiment is mounted on a vehicle equipped with an engine 10 and constitutes a lubrication system for lubricating the engine 10.

  The oil supply device includes an oil pan 11 for storing oil, and a supply path 12 for supplying oil to the engine 10. The supply path 12 has an oil reservoir 13. For example, the oil reservoir 13 is a portion bent so that the flow path of oil is positioned lower in the vertical direction than the upstream side portion and the downstream side portion of the portion, or the upstream side portion of the portion It is a larger part than the downstream part.

  The oil supply device includes an electric oil pump 14 to which a supply path 12 is connected. The electric oil pump 14 includes a motor 15 as a drive source. The electric oil pump 14 sends the oil pumped out of the oil pan 11 to the supply path 12 when the motor 15 rotates forward, and sucks the oil in the supply path 12 and discharges it to the oil pan 11 when the motor 15 reverses direction. .

  The oil supply device comprises a controller 16. The control device 16 includes a CPU 161 that performs various calculations by executing a predetermined program, and a memory 162 that stores programs of the CPU 161 and calculation results of the CPU 161.

  The oil supply device is provided with a temperature sensor 17 that detects the temperature θ of the oil stored in the oil pan 11 and outputs a detection signal indicating the detection result. The temperature sensor 17 is connected to the control device 16. The controller 16 takes in a detection signal from the temperature sensor 17.

  The controller 16 is connected to the motor 15. The control device 16 controls the drive of the motor 15 by controlling the direction of the voltage applied to the motor 15 and the magnitude thereof. The control device 16 controls the drive of the electric oil pump 14 by controlling the drive of the motor 15. That is, the control device 16 has a function as a control unit that controls the driving of the electric oil pump 14.

  Further, the control device 16 of this embodiment is configured to control the operation of the engine 10. For example, the control device 16 adjusts the injection timing by the not-shown fuel injection device provided in the engine 10, the injection amount Q thereof, and the ignition timing by the spark plug. The control device 16 may not be used as a control device for controlling the operation of the engine 10.

  Next, among the processes performed by the control device 16, an estimation process for estimating the amount of water in oil will be described. That is, the control device 16 has a function as an estimation unit that estimates the amount of water in the oil. The estimation process is repeatedly performed with a predetermined control cycle. In the following description, the estimated water content is referred to as the estimated water content W.

  As shown in FIG. 2, the control device 16 determines whether the temperature θ exceeds 100 ° C. based on the detection signal received from the temperature sensor 17 (step S <b> 10). If the temperature θ exceeds 100 ° C. (step S10: YES), the control device 16 reads the stored estimated water content W and subtracts the reduction amount ΔW2 from the read out estimated water content W to newly generate Calculate the estimated water content W. For example, the amount of decrease ΔW2 is the amount of water that evaporates from the oil per predetermined time corresponding to the control cycle, and may be a predetermined constant value, or a large value compared to when the temperature θ is high. It may be a variable value set to

  The controller 16 stores the calculated estimated water content W when the calculated estimated water content W is “0” or more. The controller 16 stores “0” as a new estimated moisture amount W when the calculated estimated moisture amount W is less than “0”. Thereafter, the control device 16 ends the estimation process.

  If the temperature θ does not exceed 100 ° C. (step S10: NO), the control device 16 reads the stored estimated water content W and adds the increase ΔW1 (Q) to the read out estimated water content W Then, a new estimated water content W is calculated. The control device 16 stores the calculated estimated moisture amount W. Thereafter, the control device 16 ends the estimation process.

  For example, the control device 16 may calculate the increase amount ΔW1 (Q) by multiplying the fuel injection amount Q by the fuel injection device by a predetermined coefficient k. Here, the injection amount Q is the amount of fuel injected from the previous control cycle to the current control cycle. Also, since mixing of water into the oil is promoted as the temperature θ is lower even if the injection amount Q is the same, the coefficient k is a variable value which is set to a large value as compared to when the temperature θ is low. It may be. For example, the control device 16 calculates the increase amount ΔW1 (Q) by referring to a map defining the relationship between the injection amount Q and the increase amount ΔW1 (Q) based on the actual injection amount Q. It is also good.

Next, among the processes performed by the control device 16, a drive process for driving the electric oil pump 14 will be described.
As shown in FIG. 3, the control device 16 determines whether the operation of the engine 10 has stopped (step S <b> 21). The stop of the operation of the engine 10 means, for example, that the rotational speed of the engine 10 has become “0” or less than a predetermined rotational speed, or that the ignition switch of the engine 10 has been switched to the off position. It can judge based on etc. When the operation of the engine 10 is not stopped (step S21: NO), the control device 16 stands by until the operation of the engine 10 is stopped. When the operation of the engine 10 is stopped (step S21: YES), the control device 16 determines whether the estimated water content W exceeds the predetermined threshold w (step S22). For example, the threshold value w is set to a value that does not clog the supply passage 12 when the water separated from the oil freezes, or a value that takes into account a predetermined safety factor with respect to the value.

  If the estimated water content W does not exceed the predetermined threshold w (step S22: NO), the control device 16 ends the drive processing. If the estimated water content W exceeds the predetermined threshold value w (step S22: YES), the control device 16 reverses the motor 15 for a predetermined period t after the operation of the engine 10 is stopped, to supply the supply path 12 The electric oil pump 14 is reversely driven so that the oil is discharged to the oil pan 11 (step S23). Thereafter, the control device 16 ends the drive processing.

  Here, immediately after the operation of the engine 10 is stopped, the oil supply path 12 is full of oil. However, as time passes after the operation of the engine 10 is stopped, oil may be naturally discharged from the supply passage 12 and air bubbles may be mixed in the oil supply passage 12. Even if the electric oil pump 14 is reversely driven so that the oil is discharged from the supply passage 12 to the oil pan 11 in a state where air bubbles are mixed in the oil supply passage 12, the oil is efficiently discharged from the supply passage 12 Can not do it. Such a problem is more pronounced when the supply passage 12 has an oil reservoir 13.

  In the oil supply device of this embodiment, the electric oil pump 14 is reversely driven for a predetermined period t from when the operation of the engine 10 is stopped, so that the oil can be efficiently supplied from the supply path 12 regardless of the presence or absence of the oil reservoir 13 It can be discharged. Therefore, clogging of the supply passage 12 caused by freezing of the water in the oil supply passage 12 can be suppressed.

  Here, for example, the predetermined period t may be set to a period until all or substantially all of the oil in the supply path 12 is discharged to the oil pan 11. The predetermined period t is predetermined based on the output of the electric oil pump 14, the volume of the supply path 12, and the like. According to this configuration, when the water in the oil freezes and clogging may occur, all or substantially all of the oil in the supply passage 12 can be discharged, and thus clogging of the oil supply passage 12 is further suppressed. can do.

In addition, the said embodiment can also be implemented, changing the structure as follows. Moreover, each modification can be combined suitably and can also be implemented.
The supply path 12 may not have the oil reservoir 13.

The oil supply device may be a device that supplies oil to the hydraulic actuator.
The control device 16 may execute the process of step S23 on condition that the outside air temperature is equal to or lower than the predetermined temperature T when the determination in step S22 is affirmative. For example, the predetermined temperature T is 0 ° C.

  The control device 16 detects the attitude of the vehicle when the determination in step S22 is affirmative, and executes the process of step S23 on condition that the detected attitude of the vehicle is a predetermined attitude. Good. For example, the posture determined in advance may be a posture in which the possibility that oil or water is collected in the oil reservoir 13 is high. The control device 16 may detect the attitude of the vehicle based on the detection signal from the gyro sensor.

  DESCRIPTION OF SYMBOLS 10 ... Engine, 11 ... Oil pan, 12 ... Supply path, 14 ... Electric oil pump, 16 ... Control apparatus, 161 ... CPU, 162 ... Memory.

Claims (2)

An oil pan for storing oil,
An electric oil pump connected to a supply path for supplying oil to an engine and delivering oil pumped out from the oil pan to the supply path;
An oil supply device including: a control unit that controls driving of the electric oil pump;
It has an estimation unit that estimates the amount of water in oil,
The control unit is configured to discharge oil from the supply path to the oil pan for a predetermined period from when the operation of the engine is stopped, on condition that the estimated water content exceeds a predetermined threshold. An oil supply device characterized by reversely driving the electric oil pump.   The estimation unit estimates that the amount of water is smaller when the temperature of the oil exceeds 100 ° C. than when the temperature of the oil does not exceed 100 ° C.
  The oil supply device according to claim 1.

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