JPH0571328A - Lubrication device of engine - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the horsepower loss due to oil in the bearing of the rotating shaft. [Structure] A bearing portion 5 that rotatably supports a rotating shaft 1 of an engine, an oil pump 10 that supplies oil to the bearing portion 5 through oil passages 9, 12, and 13, and a gas that mixes gas into the oil passages 9 and 13. The mixing means 17 and 20 are provided, and the gas mixing means 17 and 20 are controlled to mix the gas when at least one of the engine speed, the load, and the oil temperature is low.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine lubricating device for reducing horsepower loss.

[0002]

2. Description of the Related Art In a rotary shaft such as a crank shaft or a cam shaft of an engine, lubricating oil is supplied between the rotary shaft and a bearing to float the rotary shaft and reduce frictional resistance. Conventionally, the clearance area between the rotating shaft and the bearing, that is, the area of the oil film is set so that a sufficient lubrication state can be obtained even under high load and high rotation and at the expected maximum oil temperature.

[0003]

However, in the conventional method, since the oil film area is set as described above, the oil film area becomes excessively large especially at low load and low rotation, and the oil film is viscous. Excessive area became resistance and increased horsepower loss. Further, at the time of cold start, the resistance was large, and therefore the startability was not good. Furthermore, when the vehicle started to operate at high speed immediately after cold start, the oil temperature was low and resistance was still high, resulting in increased loss horsepower. The present invention solves the above problem, and an object of the present invention is to provide an engine lubrication device that can reduce the horsepower loss due to oil in the bearing portion of the rotating shaft.

[0004]

To this end, the engine lubrication apparatus of the present invention supplies oil through a bearing portion 5 that supports the rotary shaft 1 of the engine and through the oil passages 9, 12, 13 to the bearing portion 5. And a gas mixing means 17, 20 for mixing gas into the oil passages 9, 12, 13 for mixing gas when at least one of engine speed, load and oil temperature is low. The gas mixing means is controlled as described above. It should be noted that the numbers added to the above-mentioned configurations are for comparison with the drawings for easy understanding, and the configurations of the present invention are not limited thereby.

[0005]

In the present invention, when at least one of the engine speed, load and oil temperature is low, the gas mixing means is controlled so as to mix the gas into the oil passage, and the gas is supplied to the bearing together with the oil. By doing so, the viscosity of the oil is reduced by the amount of the mixed gas, so that the horsepower loss can be reduced.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of an engine lubrication device of the present invention.

A crank pin 2 connected to a connecting rod is integrally formed on the crank shaft 1. Crankshaft 1
Is rotatably supported by a bearing 5 made of metal and provided on the partition 3 of the crankcase. An oil pan 6 and an oil strainer 7 are provided in the lower part of the crankcase. The oil is sucked into the oil pump 10 through the suction oil passage 9, and the oil from the oil pump 10 passes through the oil filter 11 to the main. It is supplied to the oil passage 12. The oil in the main oil passage 12 is supplied to the bearing portion 5 of the crankshaft 1 via the respective branch oil passages 13, and further, is supplied to the crankpin 2 through the inside of the crankshaft 1. Further, the oil in the main oil passage 12 is supplied to the rotating portion and the sliding portion of the engine such as a cam shaft (not shown) via the branch oil passage 15.

An air intake passage 16 is connected to the intake oil passage 9, and the air intake passage 16 is connected to an air cleaner 19 via an air flow rate control valve 17, whereby air is introduced into the intake oil passage 9 upstream of the oil pump 10. A gas mixing means for mixing is formed. That is, the air flow control valve 17 drives the stepping motor 17a to control the opening degree of the valve body 17b steplessly according to the operating state of the engine, and the oil pump 1
With the suction force of 0, the air passes through the air cleaner 19, the air flow control valve 17, the air suction passage 16 and the suction oil passage 9
It is mixed with the oil inside. In this case, the air intake passage 16
By reducing the area of the opening to the suction oil passage 9, the bubbles are reduced and the deterioration of the lubricating performance is prevented. As the gas mixing means, the air pump 20 may be connected to the downstream side of the oil pump 10, and an inert gas such as nitrogen gas may be used instead of air.

Next, the control of the lubricating device having the above construction will be described with reference to FIGS. 2 is a block diagram of a control system according to the present invention, FIG. 3 is a diagram showing an example of a control map, and FIG. 4 is a diagram showing an example of a control flow.

In FIG. 2, signals from the engine speed sensor 22, the suction negative pressure sensor 23, the oil temperature sensor 24, and the air flow control valve opening sensor 25 are input to the electronic control unit 21. , The control map stored in advance is compared, calculated, and processed to determine the amount of air mixed in the oil, and a control signal corresponding to the determined amount is output to the air flow control valve 17. Air mixing is
As shown in FIG. 3, the control is performed so that the engine speed and the load are equal to or less than a predetermined value, and the air mixing amount is controlled to increase in accordance with the decrease in the engine speed and the load. The amount of air mixed in is controlled to increase according to the decrease in temperature.

An example of the control will be described with reference to FIG. 4. In step S1, the actual engine speed N, the suction negative pressure P and the oil temperature T are read, and in step S2, the engine speed N and the intake speed are read from the control map. It reads the target valve opening L _a of the air flow control valve 17 in response to a negative pressure P and the oil temperature T, in step S3, reads the actual valve opening L _b of the air flow control valve 17. Next, in step S4, it is determined whether or not the difference between the actual valve opening L _b and the target valve opening L _a is positive, and if positive, the process proceeds to step S8,
The control amount is determined according to the difference, and a valve closing control signal for the air flow control valve 17 is output in step S9. Step S4
In step S5, if the difference is not positive, it is determined whether or not the difference is 0. If it is 0, the process returns and the above process is repeated. If the difference is not 0, that is, it is negative, step S6. To determine the control amount according to the difference,
In step S7, a valve opening control signal for the air flow control valve 17 is output.

The present invention is not limited to the above embodiment, but various modifications can be made. For example, in the above-described embodiment, the bearing portion of the crank shaft is described as an example, but the bearing portion of another rotating shaft such as a cam shaft may be applied. Further, in the above-described embodiment, the gas mixture amount is controlled, but it is also possible to control only the gas mixture without controlling the gas mixture amount.

[0013]

As described above, according to the present invention, the gas mixing means is controlled so as to mix the gas into the oil passage when at least one of the engine speed, the load and the oil temperature is low, and the bearing Since the gas is supplied to the portion together with the oil, the viscosity of the oil is reduced by the amount of the mixed gas, and as a result, the horsepower loss can be reduced.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an engine lubricating device of the present invention.

FIG. 2 is a block diagram of a control system according to the present invention.

FIG. 3 is a diagram showing an example of a control map according to the present invention.

FIG. 4 is a diagram showing an example of a control flow according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotating shaft, 5 ... Bearing part, 9, 12, 13 ... Oil passage, 10
... Oil pumps 17 and 20 ... Gas mixing means

Claims (1)

[Claims] 1. A bearing section for rotatably supporting a rotating shaft of an engine, an oil pump for supplying oil to the bearing section through an oil passage, and gas mixing means for mixing gas into the oil passage, A lubricating device for an engine, characterized in that the gas mixing means is controlled so as to mix gas when at least one of engine speed, load and oil temperature is low.