JP5476765B2 - Lubricating device for internal combustion engine - Google Patents

Description

  The present invention relates to a lubricating device for an internal combustion engine.

  In Patent Document 1, the amount of oil supplied to a sliding part (cam, cam chain, etc.) and a cooling part (for example, a piston) of an internal combustion engine is changed according to changes in the oil temperature of the internal combustion engine and the rotational speed of the internal combustion engine. An internal combustion engine lubrication device including a supply amount control means is disclosed.

JP 2006-97491 A

  According to the technique according to Patent Document 1, overcooling of the cooling unit can be suppressed by stopping oil supply to the cooling unit while lubricating the sliding unit, for example. However, in the technique according to Patent Document 1, when oil supply to the cooling unit is stopped halfway when supplying oil to the lubrication site, the oil pressure of the oil system (hereinafter referred to as system pressure) may increase. is there. As a result, for example, torque fluctuation may occur. In addition, when the oil supply to the cooling unit is resumed, the system pressure may decrease. As a result, for example, the amount of oil supplied to the cooling unit may be insufficient.

  The present invention provides a lubricating device for an internal combustion engine that can suppress fluctuations in the system pressure that accompany stopping and resuming oil supply to a cooling unit.

A lubricating device for a first internal combustion engine according to the present invention includes a variable pump that discharges oil toward a sliding portion and a cooling portion of the internal combustion engine, and oil discharged from the variable pump toward the cooling portion. And a control valve for supplying and stopping supply of the oil discharged from the variable pump to the cooling unit, and an acquisition result of a state acquisition means for acquiring information on the operating state of the internal combustion engine. Control means for controlling the variable pump and the control valve, respectively, wherein the cooling unit is a piston of the internal combustion engine, and the control means is prior to stopping oil supply to the piston by the control valve. the output of the variable pumping controls the variable pump to reduce Te, the control means, unburnt gas running condition of the internal combustion engine from the internal combustion engine as white smoke If the condition to be issued, in terms of oil supply stop to the piston to control the said control valve to be performed, wherein an output of the variable pump to control the variable pump to increase Is.

According to the first internal combustion engine lubrication apparatus of the present invention, since the oil supply to the piston as the cooling unit is stopped after the output of the variable pump is reduced, the increase in the system pressure is suppressed. Can do. Moreover, according to this structure, the warm-up of the internal combustion engine is promoted by stopping the oil supply to the piston that is the cooling unit. Furthermore, since the load of the internal combustion engine increases as the output of the variable pump increases, warming up of the internal combustion engine is promoted. As a result, white smoke emission can be suppressed.

A second internal combustion engine lubrication apparatus according to the present invention includes a variable pump that discharges oil toward a sliding portion and a cooling portion of the internal combustion engine, and oil discharged from the variable pump toward the cooling portion. And a control valve for supplying and stopping supply of the oil discharged from the variable pump to the cooling unit, and an acquisition result of a state acquisition means for acquiring information on the operating state of the internal combustion engine. Control means for controlling the variable pump and the control valve , respectively, wherein the cooling section is a piston of the internal combustion engine, and the control means is prior to oil supply to the piston by the control valve. The variable pump is controlled so that the output of the variable pump increases.

According to the second internal combustion engine lubrication apparatus of the present invention, since the discharge oil is supplied to the piston as the cooling unit after increasing the output of the variable pump, the decrease in the system pressure is suppressed. Can do.

In the above configuration, the control unit, when the previous SL engine operating condition the internal combustion engine in a state where unburned gas is discharged as white smoke, the so oil supply stop is performed to the piston The variable pump may be controlled so that the output of the variable pump increases after controlling the control valve.

According to this configuration, the warm-up of the internal combustion engine is promoted by stopping the oil supply to the piston that is the cooling unit. Furthermore, since the load of the internal combustion engine increases as the output of the variable pump increases, warming up of the internal combustion engine is promoted. As a result, white smoke emission can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the lubrication apparatus of the internal combustion engine which can suppress the fluctuation | variation of the system pressure accompanying the oil supply stop to a cooling part and oil supply resumption can be provided.

FIG. 1 is a schematic diagram illustrating a configuration of a lubricating device for an internal combustion engine according to a first embodiment. FIG. 2 is a diagram illustrating an example of a flowchart of the correction process of the ECU. FIG. 3A is a diagram for explaining a method of calculating oil characteristics. FIG. 3B is a diagram showing the relationship between the correction amount and the hydraulic pressure. FIG. 4A is a map of reference discharge values when correction for reducing the reference discharge value is performed. FIG. 4B is a map of reference discharge values when correction for increasing the reference discharge value is performed. FIG. 5 is a diagram illustrating an example of a timing chart of the white smoke suppression process of the ECU according to the first modification of the first embodiment.

  Hereinafter, modes for carrying out the present invention will be described.

  An internal combustion engine lubrication apparatus 100 according to Embodiment 1 of the present invention will be described. FIG. 1 is a schematic diagram showing the configuration of the lubrication apparatus 100. The lubricating device 100 is a device that supplies oil to the sliding portion 200 that is a sliding portion of the internal combustion engine and the cooling portion that is a portion requiring cooling. In the present embodiment, the sliding portion 200 is, for example, a cam, a cam chain, or the like. The cooling unit is the piston 210. Lubricating apparatus 100 mainly includes variable pump 10, oil jet 20, control valve 30, various sensors (oil temperature sensor 40, hydraulic sensor 42 and rotation speed sensor 44), and ECU 50.

  The variable pump 10 is an oil pump that can change the output while discharging oil from the oil pan 220 in response to an instruction from the ECU 50. The output means at least one of the discharge amount and the discharge pressure. In the present embodiment, the variable pump 10 is a pump capable of changing the discharge amount. The oil intake port of the variable pump 10 communicates with the oil pan 220 via the first passage 60. The oil discharge port of the variable pump 10 communicates with the sliding portion 200 of the internal combustion engine via the second passage 62. Further, the discharge port of the variable pump 10 communicates with the control valve 30 and the oil jet 20 through the third passage 64.

  The oil jet 20 is a device that injects oil to the piston 210. In this embodiment, the oil jet 20 injects oil onto the lower surface of the piston 210. When oil is supplied to the piston 210, the piston 210 is cooled.

  The control valve 30 receives an instruction from the ECU 50 and adjusts the amount of oil supplied to the oil jet 20. For example, when the control valve 30 is controlled to open, oil supply from the oil jet 20 to the piston 210 is performed. When the control valve 30 is controlled to be closed, the oil supply from the oil jet 20 to the piston 210 is stopped. That is, the oil jet 20 and the control valve 30 have a function as a cooling unit oil supply state changing unit that supplies and stops supply of oil discharged from the variable pump 10 to the cooling unit (piston 210).

  The oil temperature sensor 40 acquires the temperature of the discharged oil (hereinafter referred to as oil temperature) and transmits the acquisition result to the ECU 50. The oil pressure sensor 42 acquires the pressure of the discharged oil (hereinafter referred to as oil pressure) and transmits the acquisition result to the ECU 50. In the present embodiment, the oil temperature sensor 40 and the oil pressure sensor 42 acquire the oil temperature and oil pressure of the second passage 62, but are not limited thereto.

  The rotation speed sensor 44 acquires the rotation speed of the internal combustion engine and transmits the acquisition result to the ECU 50. Thereby, the ECU 50 can acquire the rotation speed of the internal combustion engine and can know that the internal combustion engine has started. In this embodiment, the oil temperature sensor 40, the hydraulic pressure sensor 42, and the rotation speed sensor 44 have a function as a state acquisition unit that acquires information related to the operation state of the internal combustion engine.

  The ECU 50 is a microcomputer having a CPU 51, a ROM 52 and a RAM 53. In this embodiment, the ECU 50 has a map of the fuel injection amount, and adjusts the fuel injection amount of the internal combustion engine based on the map. Moreover, ECU50 acquires the information regarding a load among the information regarding the driving | running state of an internal combustion engine based on the amount of fuel injection. That is, the ECU 50 has a function as a state acquisition unit that acquires a load that is information relating to the operating state of the internal combustion engine. In addition, ECU50 may acquire the information regarding load based on an accelerator opening.

  Further, the ECU 50 functions as a control unit that controls the variable pump 10 and the control valve 30 based on the acquisition results of the oil temperature sensor 40, the hydraulic pressure sensor 42, and the rotation speed sensor 44. For example, the ECU 50 controls the variable pump 10 so that the output of the variable pump 10 becomes a predetermined value. Specifically, the ECU 50 stores a map of the discharge amount calculated in advance corresponding to the rotational speed of the internal combustion engine. Then, the ECU 50 calculates the discharge amount with reference to the discharge amount map based on the acquisition result of the rotation speed sensor 44, and controls the variable pump 10 so that the calculated discharge amount is obtained. In the present embodiment, the ECU 50 is calculated in advance corresponding to the rotational speed of the internal combustion engine when the control valve 30 is closed (that is, when the oil supply to the piston 210 by the oil jet 20 is stopped). A map of discharge amount (hereinafter referred to as a reference discharge value) is stored.

  For example, when the internal combustion engine is started, since the oil temperature is low, the viscosity of the oil increases. In this case, the startability is improved when the discharge amount of the variable pump 10 is small. Therefore, in this embodiment, the reference discharge value is set such that the discharge amount of the variable pump 10 decreases as the rotational speed of the internal combustion engine decreases. Thereby, since the discharge amount of the variable pump 10 at the start of the internal combustion engine is reduced, the startability of the internal combustion engine can be improved.

  Even when the internal combustion engine is lightly loaded during the warming-up process, the oil temperature is low, so the oil viscosity is high. Also in this case, it is preferable that the discharge amount of the variable pump 10 is small. This is because the load on the variable pump 10 is reduced. Accordingly, by setting the reference discharge value so that the discharge amount of the variable pump 10 is reduced when the internal combustion engine is lightly loaded during the warm-up process, the discharge amount of the variable pump 10 is reduced during the light load during the warm-up process. can do.

  When the ECU 50 starts the operation of the variable pump 10, the oil in the oil pan 220 passes through the first passage 60 and the second passage 62 and is supplied to the sliding portion 200. Thereby, the sliding part 200 can be lubricated with oil. When the ECU 50 controls the control valve 30 to open, the discharged oil passes through the third passage 64 and is supplied from the oil jet 20 to the piston 210. In the present embodiment, the ECU 50 operates the variable pump 10 when the control valve 30 is controlled to be opened.

  Further, the ECU 50 determines whether or not there is a cooling request for the piston 210, and when there is a cooling request for the piston 210, opens the control valve 30, and when there is no cooling request for the piston 210, closes the control valve 30. Control to turn on. Specifically, the ECU 50 determines whether or not there is a cooling request for the piston 210 based on the acquisition results of various sensors. For example, when the internal combustion engine is at a light load during the warm-up process and at a low temperature start, it is preferable that the overcooling of the piston 210 is suppressed. Therefore, in such a case, the ECU 50 determines that there is no request for cooling the piston 210 and controls the control valve 30 to be closed. Thereby, since the oil supply by the oil jet 20 is stopped, the overcooling of the piston 210 is suppressed. As a result, warm-up can be completed early. Further, the ECU 50 determines that there is a cooling request for the piston 210 after the warm-up operation, for example, and controls the control valve 30 to be opened. Thereby, the piston 210 can be cooled.

  Here, as described above, for example, it is preferable to reduce the load of the variable pump 10 by reducing the discharge amount of the variable pump 10 at a light load in the warm-up process. However, in this case, when the control valve 30 is controlled to be closed in order to suppress overcooling of the piston 210, the following problem occurs. That is, when the control valve 30 is controlled from open to closed, the oil supply amount of the oil jet 20 is lost, and therefore the oil pressure (hereinafter referred to as system pressure) of the oil system (second passage 62 and third passage 64). ) May rise. As a result, the load on the variable pump 10 may increase. Further, for example, when the control valve 30 is controlled from open to closed when the oil temperature is low, there is a possibility that torque fluctuations occur because the viscosity of the oil is high. As a result, there is a risk of deterioration of drivability and engine stall.

  Further, when the control valve 30 is controlled from being closed to being opened, the oil supply amount of the oil jet 20 is required, so that the system pressure may be reduced. As a result, for example, the oil pressure necessary for supplying oil from the oil jet 20 may not be obtained.

  Therefore, when the control valve 30 is controlled from open to closed, the ECU 50 according to the present embodiment reduces the output (discharge amount) of the variable pump 10 prior to controlling the control valve 30 to close. After executing the correction process for controlling the variable pump 10, the control valve 30 is controlled to be closed. In this case, an increase in system pressure can be suppressed. Thereby, increase of the load of the variable pump 10 and generation | occurrence | production of a torque fluctuation can be suppressed.

  Further, when controlling the control valve 30 from closed to open, the ECU 50 performs a correction process for controlling the variable pump 10 so that the output of the variable pump 10 increases prior to controlling the control valve 30 to open. After execution, the control valve 30 is controlled to be opened. In this case, a decrease in system pressure can be suppressed. Thereby, the oil required for the oil supply of the oil jet 20 can be secured.

  Next, an example of correction processing will be described. In the present embodiment, the ECU 50 executes the correction process by correcting the reference discharge value. FIG. 2 is a diagram illustrating an example of a flowchart of the correction process of the ECU 50. The ECU 50 repeatedly executes the flowchart of FIG. 2 at predetermined time intervals.

  Here, for the correction of the reference discharge value, for example, when the control valve 30 is controlled to be closed, an increase in the system pressure is suppressed, and when the control valve 30 is controlled to be opened, a decrease in the system pressure is suppressed. Any correction may be used. However, the viscosity of the oil has a different value depending on the temperature of the oil (for example, the lower the temperature, the higher the viscosity). Also, the temperature and viscosity of the oil have different values depending on the type of oil and the deterioration state. Therefore, by calculating the correction amount of the reference discharge value based on the instantaneous state information of the internal combustion engine, the increase and decrease in the system pressure can be suppressed with higher accuracy. Therefore, in step S10, the ECU 50 calculates an oil characteristic based on the oil information, and calculates a correction amount for the reference discharge value using the calculated oil characteristic.

  FIG. 3A is a diagram for explaining a method of calculating oil characteristics. The vertical axis represents the oil pressure, and the horizontal axis represents the oil temperature. For example, when the rotational speed is constant (for example, 1000 rpm), the ECU 50 calculates the oil characteristic based on the acquisition results of the oil temperature sensor 40 and the hydraulic pressure sensor 42. Specifically, the ECU 50 stores in advance a reference hydraulic pressure curve 300 that is a reference for calculating oil characteristics. For example, when the acquisition results of the oil temperature sensor 40 and the oil pressure sensor 42 are shifted upward from the reference oil pressure curve 300, the ECU 50 shifts the reference oil pressure curve 300 upward. On the other hand, the ECU 50 shifts the reference oil pressure curve 300 downward when the acquisition results of the oil temperature sensor 40 and the oil pressure sensor 42 are shifted downward from the reference oil pressure curve 300. As a result, an actual hydraulic pressure curve 302 indicating the current oil characteristic is obtained.

  Then, the ECU 50 uses the actual hydraulic pressure curve 302 to calculate a correction amount for the reference discharge value so that, for example, when the control valve 30 is controlled to be closed, an increase in the system pressure is suppressed. As a result, the correction amount and the hydraulic pressure when the control valve 30 is controlled to be closed have a relationship as shown in FIG.

  After step S10 shown in FIG. 2, the ECU 50 determines whether or not there is a cooling request for the piston 210 (step S20). Specifically, the ECU 50 determines whether or not the internal combustion engine is at a low temperature start based on the acquisition results of the oil temperature sensor 40 and the rotation speed sensor 44. For example, the ECU 50 determines that the internal combustion engine is at a low temperature start when the oil temperature sensor 40 is equal to or lower than a predetermined value and the rotation speed sensor 44 is equal to or lower than the predetermined value. As a result, when the internal combustion engine is at a low temperature start, the ECU 50 determines that there is no cooling request for the piston 210 and executes step S30. On the other hand, when the internal combustion engine is not at a low temperature start, the ECU 50 determines that there is a cooling request for the piston 210 and executes step S40.

  In step S30, the ECU 50 performs correction to decrease the reference discharge value. FIG. 4A is a map of the reference ejection value 310. The vertical axis represents the discharge amount of the variable pump 10, and the horizontal axis represents the rotational speed of the internal combustion engine. When the ECU 50 performs correction to decrease the reference discharge value 310, the ECU 50 decreases the reference discharge value 310 by the correction amount calculated in step S10. As a result, a corrected reference discharge value 312 is obtained. Note that the hatched range in FIG. 4A indicates the range of values that the corrected reference ejection value 312 can take. Next, as shown in FIG. 2, the ECU 50 ends the execution of the flowchart.

  In step S40, the ECU performs correction to increase the reference discharge value. For example, as shown in FIG. 4B, the ECU 50 sets the reference discharge value so that an oil jet required discharge value 314 that is the minimum oil discharge amount of the variable pump 10 necessary for supplying oil from the oil jet 20 is secured. Increase the correction. Specifically, the ECU 50 increases the portion of the reference discharge value 310 that is lower than the oil jet required discharge value 314 (the portion where the rotational speed is A or less) to the oil jet required discharge value 314. As a result, a corrected reference discharge value 316 is obtained. The hatched range in FIG. 4B indicates a range of values that the corrected reference discharge value 316 can take. Next, as shown in FIG. 2, the ECU 50 ends the execution of the flowchart.

  In addition, after executing the correction process, the ECU 50 controls the variable pump 10 according to the corrected reference discharge value 312 and the corrected reference discharge value 316 based on the acquisition result of the rotation speed sensor 44.

  Further, the lubricating device 100 may include a water temperature sensor disposed in a water jacket of the internal combustion engine, for example, instead of the oil temperature sensor 40. The ECU 50 may use the water temperature sensor acquisition result instead of the oil temperature sensor 40 acquisition result. Further, the ECU 50 may use a discharge pressure instead of the discharge amount.

(Modification 1)
By the way, conventionally, when an internal combustion engine is started from a low temperature state in a low-pressure environment such as a high altitude, unburned gas may be emitted as white smoke from an exhaust pipe of the internal combustion engine. Therefore, in the lubricating device 100 according to the present modification, the ECU 50 executes white smoke suppression processing when the operating state of the internal combustion engine is a state in which white smoke is released from the exhaust pipe of the internal combustion engine. Specifically, in the white smoke suppression process, the ECU 50 controls the variable pump 10 so that the output of the variable pump 10 increases after controlling the control valve 30 so that the supply of the discharge oil to the piston 210 is stopped. To do.

  In this case, warming up of the internal combustion engine is promoted by stopping supply of discharged oil to the piston 210. Furthermore, the load on the internal combustion engine increases as the output of the variable pump 10 increases. As a result, the heat generation amount of the internal combustion engine increases, so that warming up of the internal combustion engine is promoted. As a result, white smoke emission can be suppressed.

  FIG. 5 is a diagram illustrating an example of a timing chart of the white smoke suppression process of the ECU 50. In FIG. 5, the horizontal axis represents time. Before the start of the internal combustion engine, the discharge amount of the variable pump 10 (O / P) is zero. The control valve 30 is closed. Thereby, the oil supply from the oil jet (O / J) to the piston 210 is stopped.

  When the internal combustion engine starts, the rotational speed increases. As a result, the oil temperature increases. When the ECU 50 determines that the operating state of the internal combustion engine is a state in which white smoke emission occurs based on the acquisition results of the oil temperature sensor 40 and the rotation speed sensor 44 (for example, the oil temperature is equal to or lower than a predetermined temperature and the rotation speed is predetermined). In the case of the rotation speed or less), the variable pump 10 is controlled so that the oil discharge amount is increased. Specifically, the ECU 50 executes a correction process for correcting the reference discharge value so that the oil discharge amount increases. Even when the internal combustion engine starts, the control valve 30 is closed.

  Next, when the oil temperature reaches a temperature (ta) at which it is considered that no white smoke is emitted, the ECU 50 controls the variable pump 10 so that the oil discharge amount decreases. Specifically, the ECU 50 executes a correction process for correcting the corrected reference discharge value so that the oil discharge amount decreases. More specifically, the ECU 50 executes a correction process for returning the corrected reference discharge value to the reference discharge value before correction.

  Here, when the variable pump 10 is controlled so as to increase the oil discharge amount, there is a possibility that engine stall occurs. This is because the combustion of the internal combustion engine is not stable. For this reason, it is preferable that the oil discharge amount is gradually increased to such an extent that no engine stall occurs.

  Further, when the variable pump 10 is controlled so that the oil discharge amount decreases, the drivability of the internal combustion engine may be deteriorated. For this reason, it is preferable that the oil discharge amount is gradually reduced to such an extent that the drivability of the internal combustion engine does not deteriorate.

  The ECU 50 performs the various controls described in the first embodiment after executing the white smoke suppression process. Further, in the white smoke suppression process, the ECU 50 may adjust the fuel injection amount so that the fuel injection amount to the combustion chamber of the internal combustion engine increases as the output of the variable pump 10 increases. Since the amount of heat generated by the internal combustion engine is increased by increasing the fuel injection amount, warm-up of the internal combustion engine can be promoted. Thereby, white smoke emission can be further suppressed.

  In this modification, the lubrication apparatus 100 may include a water temperature sensor disposed in a water jacket of the internal combustion engine, for example, instead of the oil temperature sensor 40. The ECU 50 may use the water temperature sensor acquisition result instead of the oil temperature sensor 40 acquisition result. Further, the ECU 50 may use a discharge pressure instead of the discharge amount.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

DESCRIPTION OF SYMBOLS 10 Variable pump 20 Oil jet 30 Control valve 40 Oil temperature sensor 42 Oil pressure sensor 44 Speed sensor 50 ECU
DESCRIPTION OF SYMBOLS 100 Lubricating apparatus of an internal combustion engine 200 Sliding part 210 Piston 300 Reference hydraulic pressure curve 302 Actual hydraulic pressure curve 310 Reference discharge value 312 Corrected reference discharge value 314 Oil jet required discharge value 316 Corrected reference discharge value

Claims (3)

A variable pump that discharges oil toward the sliding part and the cooling part of the internal combustion engine;
A control valve that is disposed in a passage through which oil discharged from the variable pump toward the cooling unit passes, and that supplies and stops supply of oil discharged from the variable pump to the cooling unit;
Control means for controlling the variable pump and the control valve, respectively, based on the acquisition result of the state acquisition means for acquiring information relating to the operating state of the internal combustion engine,
The cooling part is a piston of the internal combustion engine;
The control means controls the variable pump so that the output of the variable pump is reduced before the oil supply to the piston is stopped by the control valve ,
The control means controls the control valve so that oil supply to the piston is stopped when the operating state of the internal combustion engine is a state where unburned gas is discharged as white smoke from the internal combustion engine. In the above, the variable pump is controlled so that the output of the variable pump is increased . A variable pump that discharges oil toward the sliding part and the cooling part of the internal combustion engine;
A control valve that is disposed in a passage through which oil discharged from the variable pump toward the cooling unit passes, and that supplies and stops supply of oil discharged from the variable pump to the cooling unit;
Control means for controlling the variable pump and the control valve, respectively, based on the acquisition result of the state acquisition means for acquiring information relating to the operating state of the internal combustion engine,
The cooling part is a piston of the internal combustion engine;
The lubrication device for an internal combustion engine, wherein the control means controls the variable pump so that an output of the variable pump increases prior to oil supply to the piston by the control valve. Wherein when the operating state of the previous SL internal combustion engine the internal combustion engine in a state where unburned gas is discharged as white smoke, controls the control valve so as oil supply stop is performed to the piston Then, the lubricating device for an internal combustion engine according to claim 2 , wherein the variable pump is controlled so that the output of the variable pump increases.

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