JP4534367B2 - Lubricating device for internal combustion engine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lubricating device for an internal combustion engine, in particular, an internal combustion engine in which lubricating oil in the internal combustion engine is held in a heat accumulator, and the lubricating oil kept warm at the time of restart is supplied to the engine body to promote warming up. The present invention relates to an engine lubrication device.
[0002]
[Prior art]
In the lubricating device for an internal combustion engine disclosed in Japanese Patent Laid-Open No. 4-31611, oil (lubricating oil) is sucked from an oil pan or a heat accumulator at the lower part of the engine body by an oil pump as a hydraulic source, and pressurized oil is supplied. Supplying to each part of the engine body, lubrication, cooling and driving of various hydraulic actuators. Such an internal combustion engine stores oil in an oil pan or a heat accumulator at the lower part of the engine body when the engine is stopped. In particular, in the case of adopting a configuration in which most of the oil is accommodated in the heat accumulator, the heat is kept during restart. Oil can be supplied to each part of the engine body to promote warming up of the engine.
[0003]
In other words, a heat accumulator and oil filter are installed in the external lubricating oil circulation system that connects the lubricating oil outlet and lubricating oil inlet formed in the engine body, and the oil is stored and retained in the regenerator when the engine is stopped, and the heat is retained when restarting. The supplied oil is supplied to each part of the engine to promote warming up. In this case, the oil in the heat accumulator is filtered by an oil filter by driving a lubricating oil pump, and then pumped to each part of the engine body through the lubricating oil inlet.
That is, as shown in FIG. 6 (b), in the lubricating oil circulation path R ′ of the lubricating device of the conventional internal combustion engine, the oil from the lubricating portion of the engine body is supplied to the heat accumulator by the discharge pump, and is kept warm by the heat accumulator. Oil is supplied to the lubrication part of the engine body through an oil filter by a supply pump.
[0004]
[Problems to be solved by the invention]
As described above, in the conventional internal combustion engine lubrication device disclosed in Japanese Patent Laid-Open No. 04-31611, when the engine is restarted, the oil in the heat accumulator is pumped to each part of the engine through the oil filter disposed outside the engine body. Has been.
For this reason, the oil that has been kept warm by the regenerator when the engine is restarted is cooled by passing through the oil filter, and the oil whose temperature has been lowered is supplied to the lubricating part of the engine body, etc., and warming up the oil that has been kept warm by the regenerator It cannot be used effectively.
An object of the present invention is to provide a lubrication device for an internal combustion engine that can effectively use oil retained in a heat accumulator for warming-up promotion based on the above-described problems.
[0005]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, a lubricating device for an internal combustion engine according to the invention of claim 1 includes a livestock heater that contains and retains lubricating oil, and a lubricating oil that is contained in the livestock heater. A supply pump that is driven by an electric motor to supply the lubrication part, a discharge pump that is driven by the rotation of the internal combustion engine and returns the lubricating oil supplied to the lubrication part of the internal combustion engine to the livestock heater, and An oil filter provided in an oil passage between the discharge pump and the livestock heat generator, and a control means for driving the supply pump when the engine speed exceeds the start determination speed ,
The control means is characterized in that, when the internal combustion engine enters an engine stop process, the supply pump is stopped when the engine rotational speed falls below a stop determination rotational speed set larger than the start determination rotational speed. To do.
[0006]
Thus, since the stop determination rotation speed is set larger than the start determination rotation speed, the supply pump is stopped early to stop the discharge of the oil in the heat accumulator, and the discharge pump is driven in the meantime, and the oil is stored in the heat accumulator. The heat accumulator can store relatively high temperature oil, keeps the oil warm until the next restart, and the supply pump keeps the oil kept warm at the time of restart to promote warming up at the time of restart it can.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an overall configuration diagram of a lubricating device for an internal combustion engine as an embodiment of the present invention.
In this internal combustion engine lubrication device, a lubricating oil circulation path R is disposed over an engine body 2 of a multi-cylinder engine (hereinafter simply referred to as an engine) 1 and the outside thereof, and the inside of the engine body 2 is illustrated via the path R. Oil (lubricating oil) is circulated and supplied to the sliding parts and various hydraulic actuators.
[0008]
As shown in FIGS. 1 and 2, the engine body 2 includes a cylinder 3, a piston 4 that slides inside the cylinder 3, a valve device 6 that flows in the intake air into the combustion chamber 5 above the piston 4 and discharges the exhaust, and the piston A lower crank chamber 7 and a relatively small-capacity oil pan 8 as a lower oil reservoir below the lower chamber are provided. A discharge pump 11 that is driven by the rotation of the crankshaft 9 is attached to the lower portion of the engine body 2. The pump 11 sucks oil from the oil pan 8 and discharges it from the outlet 12 of the engine body 2. .
As shown in FIG. 2, a branch pipe 13 is formed to extend in an internal pipe connecting the discharge port 111 of the discharge pump 11 and the outlet 12 of the engine body 2, and a relief valve 14 is attached to the branch pipe 13. It is done. The relief valve 14 includes a sphere 142 that is urged to close by a spring 141. When the sphere 142 receives a hydraulic pressure that exceeds the set hydraulic pressure of the discharge port 111, the spring 141 elastically deforms to open the short-circuit port 131, An excessive increase in pressure oil from the discharge pump 11 is prevented.
[0009]
An inlet 15 for the lubricating oil circulation path R is formed in the engine body 2. The inflow port 15 guides the pressure oil flowing into the branch passages 17 through the internal circulation main passages 16, and slides (not shown) of the cylinders 3 and the valve devices 6 (see FIG. 2) at the ends of the branch passages 17. Oil is supplied to the part or various hydraulic actuators (not shown).
As shown in FIG. 2, the engine main body 2 has an external outflow path r1 that forms part of the lubricating oil circulation path R extending from the outflow port 12, and the external discharge path r1 includes an oil filter 18 and a heat accumulator. 19 (see FIG. 6A). The oil filter 18 is integrally coupled to the outer wall of the engine body 2 by fastening fastening means (not shown), receives pressure oil from a filter inlet 21 communicating with the outlet 12, filters the oil, and then filters the oil outlet 22. More filtered oil flows out to the heat accumulator 19.
[0010]
The heat accumulator 19 is a container-like member having a capacity capable of accommodating most of the oil flowing down to the oil pan 8 when the engine is stopped. The heat accumulator 19 is integrally tightened and connected to the outer wall portion of the engine body 2 with a mounting bolt (not shown). Yes. The oil discharged from the discharge pump 11 is pumped to the external discharge path r1, and the oil is smoothly supplied to the oil filter 18 and the heat accumulator 19 on the external discharge path r1 regardless of the relative vertical position. Is done. That is, the heat accumulator 19 here is arranged at a high position by H in the vertical direction with respect to the oil pan 8, but pressure oil is smoothly supplied to the heat accumulator 19.
[0011]
For this reason, the heat accumulator 19 has a sufficient degree of freedom in the arrangement position in the vertical direction. In addition, since the heat accumulator 19 having a sufficient lubricating oil accommodating space is disposed at a relatively upper position independently of the engine body 2, the volume of the oil pan 8 as the lower oil reservoir may be extremely small. 2 can be suppressed, the position of the center of gravity of the engine body can be lowered, and the running stability can be improved.
As shown in FIGS. 1 and 3, the heat accumulator 19 has a double structure of an outer wall member 23 that forms an outer case and a heat insulating wall 24 that forms an inner case inside thereof, and is accommodated by the action of the heat insulating wall 24. The oil insulation function is secured. The heat insulating wall material may be in the shape of a heat insulating bottle with a reflective film, or a multilayer heat insulating wall material including a heat insulating material in the middle in the thickness direction or a vacuum between the outer wall material and the inner wall material. It may be.
[0012]
A container outlet 25 is formed in the container lower wall portion 191 of the heat accumulator 19, and an inlet 261 of a supply pump 26 disposed at substantially the same vertical position as the container lower wall portion 191 is communicated with the container outlet 25. Yes. As shown in FIG. 2, the pump discharge port 262 of the supply pump 26 is connected to the inlet 15 of the engine body 2 via the external return path r2. The supply pump 26 is directly connected to an electric motor 27, and the electric motor 27 is connected to a controller 29 via a drive circuit 28.
[0013]
The controller 29 connects the rotation sensor 31 that outputs the rotation speed signal Ne of the engine 1 and the hydraulic sensor 32 that outputs the hydraulic signal Po of the internal circulation main path 16 and functions to drive the supply pump 26 in a predetermined mode. . That is, the controller 29 always takes in the engine speed Ne and the hydraulic signal Po of the discharge port 262, and when the engine speed Ne enters a region exceeding the start determination speed Ne1, drives the supply pump 26 at the set speed and stops the engine. The pump is stopped when it falls below the stop determination rotational speed Ne2 during processing. Here, the stop determination rotation speed Ne2 (> Ne1) is set larger than the start determination rotation speed Ne1. This prevents hunting at the time of control, stops the supply pump 26 relatively quickly when the engine stop process is started, stops the oil outflow of the heat accumulator 19, and ensures the amount of lubricating oil accommodated in the heat accumulator 19. Plan.
Further, the controller 29 has a pump control function that stops the supply pump 26 when the hydraulic signal Po of the internal circulation main path 16 exceeds the set hydraulic pressure Po1, and drives the supply pump 26 again when the hydraulic signal Po falls below.
[0014]
A schematic configuration of the lubricating oil circulation path R of the lubricating device for the internal combustion engine of FIG. 1 is shown in FIG.
In this lubricating oil circulation path R, oil from the engine body is supplied to the heat accumulator 19 via the oil filter 18 by the discharge pump 11, and oil retained by the heat accumulator 19 is supplied to the lubrication part of the engine body 2 by the supply pump 26. From this, it is apparent that the oil retained by the heat accumulator 19 can be effectively used to promote warming of the lubrication part of the engine body 2. For reference, the oil that has been kept warm by the heat accumulator is radiated by the oil filter when guided to the lubricating part of the engine body 2 as in the lubricating oil circulation path R ′ of the conventional lubricating device shown in FIG. Can be avoided.
[0015]
In such a lubricating device for an internal combustion engine, the controller 29 is driven when the engine is started, and the pump driving routine of FIG. 5 is executed. The controller 29 fetches the engine speed Ne and the hydraulic signal Po of the internal circulation main path 16 in steps s1 and s2, and then confirms that the engine stop process is not entered, that is, the engine main switch (not shown) is not turned off. After confirming this, step s3 is reached. Here, if the engine speed Ne exceeds the start determination speed Ne1, the process proceeds to step s4. When cranking the engine speed Ne below the start determination speed Ne1 in step s3, the process proceeds to step s6, and the supply pump 26 is held stopped.
[0016]
When the engine rotational speed Ne exceeds the start determination rotational speed Ne1, the process proceeds to step s4. Here, it is determined whether or not the hydraulic signal Po of the internal circulation main path 16 exceeds the set hydraulic pressure Po1, and when it falls, the process proceeds to step s5. The supply pump 26 is driven. As a result, the supply pump 26 pressurizes the oil kept in the heat accumulator 19, and the oil is supplied to the external return path r <b> 2 from the pump discharge port 262 and from the inlet 15 of the engine body 2 to the internal circulation main path 16 and each branch path. 17 is supplied to the sliding portions of the cylinder 3 and the valve device 6 or various hydraulic actuators (not shown) to lubricate or hydraulically operate these parts, and to promote warming of these parts.
[0017]
When the engine is started, the discharge pump 11 that rotates in synchronization with the crankshaft 9 rotates in synchronization with the engine and discharges, and supplies discharged oil to the heat accumulator 19 through the oil filter 18. At this time, the oil that has been kept warm by the supply pump 26 that is driven to discharge when the engine speed exceeds the start determination rotational speed Ne1 is supplied to the cylinders 3 of the engine body 2 and the sliding parts (not shown) of the valve device 6 or various hydraulic actuators. Then, warming up of these parts is promoted. In such a state, oil from the oil filter 18 side sequentially flows into the heat accumulator 19 having a relatively large capacity, is heated by the inner wall surface of the same part, and is discharged to the engine body 2 side. Become.
On the other hand, when the hydraulic pressure signal Po exceeds the set hydraulic pressure Po1 set to determine whether or not the hydraulic pressure signal Po has reached an excessive hydraulic pressure value in step s4, the process proceeds to step s6, the supply pump 26 is stopped, and the internal circulation main path The situation in which the hydraulic pressure of 16 or the branch path 17 excessively increases is avoided, and the durability of the supply pump 26 and the electric motor 27 is ensured.
[0018]
When it is confirmed in step s2 that the engine main switch (not shown) is turned off and the engine stop process is started, the process proceeds to step s7, and it is determined whether or not the engine rotation Ne is below the stop determination rotation speed Ne2 (> Ne1). If not, the process proceeds to step s5 to drive the supply pump 26, and if the value is lower, the process proceeds to step s6 and the supply pump 26 is stopped. In this case, since the stop determination rotation speed Ne2 is set to be larger than the start determination rotation speed Ne1, the supply pump 26 is stopped early and the discharge of oil from the heat accumulator 19 is stopped. On the other hand, since the discharge pump 11 that operates in synchronization with the engine is driven until the engine rotation is completely stopped, the oil flowing down to the oil pan 8 at the lower part of the engine body is sent to the heat accumulator 19 through the oil filter 18, A relatively high temperature oil can be accommodated in the heat accumulator 19 whose supply pump is stopped and the outflow is stopped.
[0019]
By such oil pump control, the relatively high temperature oil contained in the heat accumulator 19 is prevented from releasing heat by the action of the heat insulating layer 24, and the oil is kept warm until the next restart. The supplied oil can be supplied into the engine to promote warm-up during restart.
In the continuous operation state of the engine 1, if the engine speed Ne increases excessively, the discharge amount of the discharge pump 11 increases rapidly. In this case, when the hydraulic pressure at the discharge port 111 of the discharge pump 11 exceeds the set hydraulic pressure, relief is performed. The spherical body 142 of the valve 14 is opened to open the short-circuit port 131, and the oil discharged excessively by the discharge pump 11 is returned to the oil pan 8, thereby preventing the oil pressure of the oil filter 18 and the heat accumulator 19 from increasing.
[0020]
1, the supply pump 26 is connected to the container outlet 25 of the heat accumulator 19, but instead, the supply pump 26 is supplied to the low wall 191a of the heat accumulator 19a as shown in FIG. A pump 26a may be installed so that the discharge port 262a of the supply pump 26a communicates with the container outlet 25a. In this case, it is easy to secure the installation space for the supply pump 26a, the installation work is facilitated, and the cost of the lubricating device for the internal combustion engine can be reduced.
In the internal combustion engine lubrication apparatus of FIG. 1, the heat accumulator 19 is integrally attached to the outer wall of the engine body 2, but in some cases, the heat accumulator 19 is attached to the inner wall member side of the engine room and disposed independently. In this case, the same effect as the lubricating device for the internal combustion engine of FIG. 1 can be obtained. Further, in the lubricating device for the internal combustion engine of FIG. 1, the discharge pump is driven by the crankshaft, but it may be driven by an electric pump, and the supply pump may be driven by the engine instead of the electric pump.
[0021]
【The invention's effect】
As described above, according to the first aspect of the present invention, the oil that has been kept warm by the livestock heater is directly supplied to the lubricating portion of the engine body without passing through the oil filter, and the temperature of the kept warm oil is suppressed. The oil that can be supplied to the lubrication part and kept in the heat accumulator can be effectively used to promote warm air. In addition, by returning the oil in the engine body to the heat storage device via the oil filter by the discharge pump, the effect of increasing the degree of freedom in the vertical direction of the placement position of the heat storage device can be obtained, and mounting can be facilitated.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an engine equipped with a lubricating device for an internal combustion engine according to an embodiment of the present invention.
2 is a schematic configuration diagram in which an oil filter, a heat accumulator, and a supply pump are separated from an outer wall of an engine body and a lubricating oil circulation path is clarified in a cross-sectional view of a main part of the engine of FIG.
3 is an enlarged cutaway cross-sectional view of a heat accumulator and a supply pump used in the lubricating device for the internal combustion engine of FIG. 1. FIG.
4 is an enlarged cutaway cross-sectional view of a modification of the regenerator and supply pump of FIG.
FIG. 5 is a flowchart of a pump drive routine performed by a controller of the internal combustion engine lubrication device of FIG. 1;
6A and 6B are schematic configuration diagrams of a lubricating oil circulation path of a lubricating device for an internal combustion engine, in which FIG. 6A shows the lubricating oil circulation path of FIG. 1 and FIG. 6B shows a conventional lubricating oil circulation path.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Engine 2 Engine main body 11 Discharge pump 18 Oil filter 19 Livestock heater 26 Supply pump r1 External outflow path (oil path)
R Lubricating oil circuit

Claims (1)

A livestock heater that contains and keeps the lubricating oil, a supply pump that is driven by an electric motor to supply the lubricating oil contained in the livestock heater to the lubrication part of the internal combustion engine, and the rotation of the internal combustion engine A discharge pump for returning the lubricating oil supplied to the lubrication part of the internal combustion engine to the livestock heater, an oil filter provided in an oil passage between the exhaust pump and the livestock heater, and engine rotation Control means for driving the supply pump when the number exceeds the start determination rotation speed ,
When the internal combustion engine enters an engine stop process, the control means stops the supply pump when the engine speed falls below a stop determination speed set larger than the start determination speed. A lubricating device for an internal combustion engine.

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