KR19990057254A - Piston Cooling System and Control Method of Vehicle - Google Patents

Abstract

The present invention relates to a piston cooling device and a control method of a vehicle for optimizing cooling performance by adjusting an injection amount of cooling oil injected to a piston based on the actual temperature of the piston to cool the piston. An oil pump 30 for pumping oil stored in the oil pan 16 of the oil pump, an injection nozzle 34 for ejecting oil pumped from the oil pump 30 to the piston 12, and an oil pump 30. Flow meter 20 for measuring the amount of oil flowing into the injection nozzle 34, rpm sensor 50 for measuring the number of revolutions of the engine, cooling water temperature sensor 60 for measuring the temperature of the coolant and , Oil pump (30) for measuring the temperature of the oil, the rpm sensor 50, the coolant temperature sensor 60, the oil temperature sensor 70 and the flow meter 20 to receive the value of the oil pump (30) Oil pump control unit 40 for controlling the amount of pumping) By controlling the amount of oil injected into the piston 12 according to the measured temperature of the piston 12, there is an advantage that the optimum cooling performance can be exhibited.

Description

Piston Cooling System and Control Method of Vehicle

The present invention relates to a piston cooling device and a control method of a vehicle, and more particularly, to optimize a cooling performance by adjusting an injection amount of cooling oil injected into a piston based on the actual temperature of the piston to cool the piston. It relates to a piston cooling device and a control method of the.

The car is a very complex structure, but the car is divided into a chassis and a body. The chassis consists of a frame, an engine, a power transmission device, a suspension device, a steering device, a brake device, and the like, as parts and devices of the rest of the body removed from the vehicle.

There are a cylinder, a cylinder head, a piston, etc., which are components for forming the engine, and various devices such as a valve device, a lubrication device, a cooling device, a fuel device, an ignition device, and a starting device are combined. Since the combustion gas temperature in the cylinder reaches 2,000 ° C. or more, a significant amount of this heat is conducted to the cylinder, cylinder head, piston, valve, and the like. Excessively high temperatures in these parts reduce the strength of the part material, cause failures or shorten their lifespan, and result in knocking and premature ignition, resulting in lower engine output. In addition, in the incomplete cooling state, failures such as abnormal lubrication and seizure may occur due to deterioration of lubrication function such as breaking of the oil film on the cylinder wall and deterioration of oil.

On the contrary, if the cooling is excessively high, the amount of heat lost by cooling is large among the heat generated from combustion, and thus, the engine thermal efficiency is lowered and the fuel consumption is increased. Therefore, the function of the cooling device is to maintain the engine temperature properly. . The engine cooling system includes an air-cooling type in which the engine is directly cooled by external air, and a water cooling type in which cooling water is circulated to cool the engine.

The water-cooled chiller is to cool the engine by using the coolant to circulate the coolant in the water jacket provided in the cylinder block and the cylinder head to the cooling function, the main part of the radiator, water pump, cooling fan, water temperature controller, etc. It consists of. The coolant turns the water pump to send the coolant to the water jacket of the cylinder block and the cylinder head, and then sends the heated coolant to the radiator to dissipate and circulate it back to the water jacket. Cooling fan is attached to the water pump to force the outside air through the radiator to improve the heat dissipation effect. And a water temperature controller is installed between the water jacket and the radiator to adjust the temperature by changing the circulation path of the cooling water according to the temperature.

However, there is a problem that the cooling by the water jacket can not achieve the optimal cooling performance because it is controlled by the temperature of the cooling water regardless of the actual piston temperature.

The present invention was created to solve the above problems, an object of the present invention is to adjust the injection amount of the oil for cooling the piston according to the output state of the vehicle and the actual temperature of the piston to achieve the optimal cooling performance. The present invention provides a piston cooling apparatus and a control method of a vehicle.

1 is a block diagram schematically showing a piston cooling apparatus of a vehicle according to the present invention.

2 is a flowchart illustrating a method of controlling a piston cooling device of a vehicle according to the present invention step by step.

-Explanation of symbols for the main parts of the drawings-

10 cylinder 20 flow meter

30: oil pump 40: oil pump control unit

50: rpm sensor 60: cooling water temperature sensor

70: oil temperature sensor

In order to achieve the above object, the piston cooling device of the vehicle of the present invention includes an oil pump for pumping oil stored in an oil pan under the cylinder, an injection nozzle for ejecting oil pumped from the oil pump to the piston, Flow meter for measuring the amount of oil flowing from the oil pump to the injection nozzle, rpm sensor for measuring the engine speed, coolant temperature sensor for measuring the temperature of the coolant, oil temperature for measuring the oil temperature It consists of an oil pump control unit for controlling the pumping amount of the oil pump by inputting the sensor, rpm sensor, cooling water temperature sensor, oil temperature sensor and flow meter.

In addition, the method of controlling the piston cooling device of the vehicle includes measuring an engine speed, a cooling water temperature (Tw) and an oil temperature (Toil) by using an rpm sensor, a cooling water temperature sensor, and an oil temperature sensor, and spraying the injection nozzle through a flow meter. Measuring the injection amount (Qoil) of the oil injected through, Computing the crown temperature (Tp, crown) of the piston and the ring temperature (Tp, ring) of the piston, Crown temperature (Tp, crown) of the measured piston ) And comparing the crown temperature (Ts, crown) of the initially set piston, and the measured piston ring temperature (Ts, crown) when the measured piston crown temperature (Tp, crown) is smaller than the initially set piston crown temperature (Ts, crown). Comparing Tp, ring) with the limit temperature (Ts, ring) of the piston ring, and if the measured piston ring temperature (Tp, ring) is smaller than the limit temperature (Ts, ring) of the piston ring, Setting the rpm of the pump to the minimum and setting it to the minimum. Operating the oil pump at a predetermined rotational speed (Prpm) of the oil pump and comparing the crown temperature (Tp, crown) of the piston with the initial set crown temperature (Ts, crown) of the measured piston crown temperature (Tp, the measured piston ring temperature (Tp) as a result of comparing the measured piston ring temperature (Tp, ring) to the piston ring limit temperature (Ts, ring) when the crown is greater than the initial set piston crown temperature (Ts, crown). If the ring is greater than the limit temperature (Ts, ring) of the piston ring, calculating the temperature difference (ΔT) of the value compared with the measured value, and the oil injection amount (C) to cool the calculated temperature difference (ΔT) Calculating and determining the number of revolutions (Prpm) of the oil pump (30) for injecting the calculated amount of oil injection (Qoil), and according to the set number of revolutions (Prpm) of the oil pump Start the oil pump and change the engine speed, coolant temperature (Tw) and oil temperature (Toil). It is a step returned to the measuring step.

The present invention made as described above is a flow meter and the operating state of the engine and the temperature of the coolant to measure the actual amount of the injection amount injected into the piston through the injection nozzle by pumping the oil stored in the oil pan 16 through the oil pump And after predicting the actual temperature of the piston by measuring the temperature of the oil to determine the amount of oil to be injected and by controlling the operating amount of the oil pump to adjust the optimum cooling performance to cool the piston.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In addition, this embodiment is not intended to limit the scope of the present invention, but is presented by way of example only.

1 is a block diagram showing a piston cooling device of a vehicle according to an embodiment of the present invention.

As shown in FIG. 1, a water jacket 14 is provided on the body of the cylinder 10, and an oil pan 16 for storing oil is installed below the cylinder 10. And the oil pump 30 for pumping the oil of the oil pan 16 is connected through the suction pipe 32 and the injection nozzle 34 for injecting the oil pumped from the oil pump 30 to the piston 12 There is this. A flow meter 20 is installed between the oil pump 30 and the injection nozzle 34 to measure the amount of oil to be injected.

And the oil pump control unit 40 for controlling the operation of the oil pump 30 is electrically connected to the oil pump 30, the oil pump control unit 40 is an rpm sensor 50 for measuring the rotational speed of the engine ), A coolant temperature sensor 60 for measuring the water temperature of the engine coolant, an oil temperature sensor 70 for measuring the temperature of the oil stored in the oil pan 16, the flow meter 20 mentioned above, It is electrically connected to each other to control the operation of the oil pump 30 by calculating the crown temperature and the ring temperature of the piston 12.

When explaining the operation of the present embodiment made as described above with reference to the flow chart showing the operation sequence of the piston cooling device of the vehicle shown in FIG.

First, the engine speed, the cooling water temperature (Tw) and the oil temperature (Toil) of the engine are measured through the rpm sensor 50, the cooling water temperature sensor 60, and the oil temperature sensor 70. In addition, the injection amount Qoil of oil injected through the injection nozzle 34 is measured through the flow meter 20 (S20).

Then, the crown temperature Tp (crown) of the piston 12 is calculated from the value measured by the oil pump control unit 40 to calculate the actual ring temperature (Tp, ring) of the piston 12 (S30). Then, the crown temperature Tp, crow of the measured piston 12 is compared with the crown temperature Ts, crown of the piston 12 which is initially set (S40). At this time, when the measured piston 12 crown temperature (Tp, crown) is smaller than the initial set piston 12 crown temperature (Ts, crown), the measured piston 12 ring temperature (Tp, ring) and the piston 12 Compare with the limit temperature (Ts, ring) of the ring (S50).

As a result of comparison, when the measured piston 12 ring temperature (Tp, ring) is smaller than the limit temperature (Ts, ring) of the piston 12 ring, the rotation speed (Prpm) of the oil pump 30 is set to '0'. Set (S60). When the oil pump 30 is operated, since the rotation speed Prpm of the oil pump 30 is set to 0, the oil pump 30 is not operated (S100).

Then, the piston 12 in which the crown temperature Tp and crown of the piston 12 is initialized by comparing the crown temperature Tp and crown of the piston 12 with the crown temperature Ts and crown of the piston 12 initialized is initialized. ) The measured piston (12) is larger than the crown temperature (Ts, crown) and compared with the measured piston (12) ring temperature (Tp, ring) and the limit temperature (Ts, ring) of the piston (12) ring. When the ring temperature (Tp, ring) is greater than the limit temperature (Ts, ring) of the piston 12 ring, the temperature difference ΔT of the value compared with the measured value is calculated (S70). The oil injection amount Qoil for cooling the calculated temperature difference ΔT is calculated (S80). And it is determined by calculating the rotational speed (Prpm) of the oil pump 30 for injecting the calculated oil injection amount (Qoil) (S90). Then, the oil pump 30 is operated according to the rotation speed Prpm of the set oil pump 30, and the engine speed and cooling water temperature Tw and the oil temperature Toil are returned to step S10. S100).

By operating the oil pump 30 as described above, by controlling the actual piston 12 temperature by predicting the piston 12 temperature as the engine speed and the temperature of the oil and the cooling water, the oil injection amount is controlled according to the cooling state. Ensure optimal cooling performance.

As described above, the present invention measures the rotational speed of the engine, the temperature of the oil, the temperature of the cooling water, and the amount of oil injected into the piston to predict the actual measurement temperature of the piston, and compares the actual piston temperature with the reference temperature to be injected into the piston. There is an advantage that the optimum cooling performance can be exhibited by adjusting the amount of oil to be the operating amount of the oil pump.

Claims (2)

An oil pump 30 for pumping oil stored in the oil pan 16 under the cylinder 10, Injection nozzle 34 for ejecting the oil pumped from the oil pump 30 to the piston 12, Flow meter 20 for measuring the amount of oil flowing from the oil pump 30 to the injection nozzle 34, Rpm sensor 50 for measuring the rotational speed of the engine, Cooling water temperature sensor 60 for measuring the temperature of the cooling water, Oil temperature sensor 70 for measuring the temperature of the oil, Oil pump control unit for controlling the pumping amount of the oil pump 30 receives the values of the rpm sensor 50, the cooling water temperature sensor 60, the oil temperature sensor 70 and the flow meter 20 40 Piston cooling device of a vehicle, characterized in that consisting of. measuring the rotation speed of the engine, the cooling water temperature (Tw), and the oil temperature (Toil) through the rpm sensor 50, the cooling water temperature sensor 60, and the oil temperature sensor 70; Measuring an injection amount Qoil of oil injected through the injection nozzle 34 through the flow meter 20 (S20), Computing the crown temperature (Tp, crown) of the piston 12 and the ring temperature (Tp, ring) of the piston 12 (S30), Comparing the crown temperature (Tp, crown) of the measured piston 12 and the crown temperature (Ts, crown) of the piston 12 is initially set (S40), When the measured piston 12 crown temperature Tp, crown is smaller than the initial set piston 12 crown temperature Ts, crown, the measured piston 12 ring temperature Tp, ring and piston 12 ) Comparing with the limit temperature (Ts, ring) of the ring (S50), As a result of comparison, when the measured piston 12 ring temperature (Tp, ring) is smaller than the limit temperature (Ts, ring) of the piston 12 ring, the rotation speed (Prpm) of the oil pump 30 is set to the minimum. Step (S60) and Operating the oil pump 30 at a rotation speed Prpm of the oil pump 30 set to the minimum (S100); Compared to the crown temperature (Tp, crown) of the measured piston 12 and the crown temperature (Ts, crown) of the initially set piston 12, the measured piston 12 crown temperature (Tp, crown) is initialized When the piston 12 is larger than the crown temperature Ts and crown, and the measured piston 12 ring temperature Tp, ring and the limit temperature Ts, ring of the piston 12 ring, the actual measurement is performed. If the piston 12 ring temperature (Tp, ring) is greater than the limit temperature (Ts, ring) of the piston 12 ring (S70) and calculating the temperature difference (ΔT) of the value compared with the measured value and , Calculating an oil injection amount Qoil for cooling the calculated temperature difference ΔT (S80), Calculating and determining the rotation speed Prpm of the oil pump 30 for injecting the calculated oil injection amount Qoil (S90); Operating the oil pump 30 in accordance with the rotation speed (Prpm) of the set oil pump 30 and returns to the step (S10) of measuring the engine speed and cooling water temperature (Tw) and oil temperature (Toil) ( S100) Piston cooling device control method of a vehicle, characterized in that consisting of.