JP2013170451A - Abnormality determination device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an abnormality determination device for an internal combustion engine capable of detecting the shortage of oil stored in an oil storage means early.SOLUTION: In an engine 2, oil pumps 32, 33 are driven so that the pressure pulsation of oil discharged from the oil pump 33 has an opposite phase with respect to the pressure pulsation of oil discharged from the oil pump 32. An abnormality determination device 4 includes: a hydraulic sensor 42 disposed downstream of the oil pump 33 and detecting the pressure of oil discharged from the oil pump 33; and an ECU 41 determining a hydraulic pressure abnormality under a condition that a fluctuation width of the pressure pulsation of oil discharged from the oil pump 33 exceeds a predetermined threshold based on the detection information of the hydraulic sensor 42.

Description

  The present invention relates to an abnormality determination device for an internal combustion engine, and more particularly to an abnormality determination device for an internal combustion engine that determines an abnormality in hydraulic pressure caused by a decrease in oil level.

2. Description of the Related Art Conventionally, there is known an oil supply device for an internal combustion engine that includes a mechanical oil pump that discharges oil stored in an oil pan and supplies the oil to a supply site.
Normally, the supplied parts of the internal combustion engine include hydraulic drive parts mounted on the internal combustion engine such as a hydraulic variable valve mechanism and a hydraulic lash adjuster of the valve system, and sliding parts such as a crankshaft and a camshaft. It consists of

  The oil discharged from the oil pump is supplied to the plurality of supplied parts through an oil supply path in the order of, for example, a hydraulic variable valve mechanism, a hydraulic lash adjuster, and a sliding part of the internal combustion engine.

  By the way, hydraulic drive parts such as these hydraulic variable valve mechanisms and valve hydraulic lash adjusters may need to supply a large amount of oil at a high pressure when the engine is running at a low speed. However, if a large amount of oil is supplied to the hydraulically driven component at a high pressure in accordance with such a demand, excessive oil is supplied to the normal sliding portion.

  Such excessive oil supply contributes to an increase in the driving resistance of the internal combustion engine, and an increase in the size of the oil pump is inevitable in order to secure an oil supply capacity sufficient to meet this requirement. .

  For this reason, it is possible to supply a large amount of oil to a hydraulic drive component at a high pressure while preventing an excessive amount of oil from being supplied to the sliding portion without causing an increase in size of the mechanical oil pump. As an example, a lubricating device for an internal combustion engine described in Patent Document 1 is known.

  This internal combustion engine lubrication device includes a mechanical oil pump that supplies oil to an engine lubrication site (sliding site) such as a camshaft, and hydraulically variable high-pressure oil that is relieved after the mechanical oil pump is pressurized. And an electric oil pump that supplies the valve mechanism.

  In this internal combustion engine lubrication device, oil is supplied from the electric oil pump to the hydraulic variable valve mechanism in addition to a part of the oil supplied to the engine lubrication part. High pressure oil can be supplied to the hydraulic variable valve mechanism even when the engine is running at low speed.

  By the way, trochoid pumps and gear pumps are frequently used as mechanical oil pumps and electric oil pumps. For example, in the trochoid pump, the center of the inner rotor and the outer rotor are eccentric from each other, and the number of teeth of the inner rotor is one less than the number of teeth of the outer rotor. Performs pumping action.

Since the space between one rotor faces the discharge port in a compressed state, high-pressure oil is discharged during discharge. When the next space between the rotors faces the discharge port, the high pressure oil is discharged again. Then, the pressure is low between the discharge of the high pressure oil and the next discharge of the high pressure oil.
Therefore, pressure fluctuations, that is, pressure pulsations are generated by alternately repeating the hydraulic pressure to a high pressure and a low pressure as the rotor rotates.

  On the other hand, normally, the oil stored in the oil pan is recovered to the oil pan after being supplied to the supply site by the oil pump. However, if the amount of oil stored in the oil pan is small, it is recovered to the oil pan. The oil recovery efficiency is deteriorated, and the oil level (oil level height) stored in the oil pan is reduced relative to the appropriate amount, that is, insufficient.

  When the oil level decreases in this way, the strainer for sucking oil from the oil pan toward the oil pump may be in a state of sucking air (hereinafter, this state is referred to as air sucking).

  It is known that when an oil pump is in an air sucking state, the oil pump bites bubbles, so-called air biting, and pressure fluctuation due to air biting, that is, pressure pulsation occurs (for example, Patent Document 2).

  This pressure pulsation when sucking air causes the pressure pulsation due to vibration generated when the oil pump bites the bubbles, and this pressure pulsation is caused by the bubble biting when the amount of oil is small. The fluctuation range is smaller than the pressure pulsation when the oil level in the pan is normal.

JP 2004-44542 A JP 2011-174423 A

  However, in such a lubrication device for a conventional internal combustion engine, the mechanical oil pump and the electric oil pump generate pressure pulsation. Can not be distinguished. Therefore, it cannot be detected early that the oil level stored in the oil pan has decreased. As a result, there is a risk that seizure of the sliding portion may occur or the behavior of the hydraulically driven component may deteriorate.

  The present invention has been made to solve the above-described conventional problems, and provides an abnormality determination device for an internal combustion engine capable of detecting at an early stage that the oil stored in the oil storage means is insufficient. For the purpose.

  In order to achieve the above object, an abnormality determination device for an internal combustion engine according to the present invention includes: (1) a first oil pump that supplies oil stored in an oil storage means to a first supply site; The second oil pump is provided downstream of the first oil pump, is driven at the same speed as the first oil pump, and supplies the oil supplied from the first oil pump to the second supply site. The oil pump and the first oil pump and the first oil pump so that the pressure pulsation of oil discharged from the second oil pump is in reverse phase with respect to the pressure pulsation of oil discharged from the first oil pump. 2 is an abnormality determination device provided in an internal combustion engine in which the second oil pump is driven, and is provided on the downstream side of the second oil pump, and detects the pressure of oil discharged from the second oil pump. On the condition that the fluctuation range of the pressure pulsation of the oil discharged from the second oil pump exceeds a predetermined threshold based on the detection information of the oil pressure detecting means and the oil pressure detecting means It is comprised from the thing provided with the abnormality determination means to determine.

  The internal combustion engine includes the first oil pump and the second oil pump so that the pressure pulsation of the oil discharged from the second oil pump is opposite in phase to the pressure pulsation of the oil discharged from the first oil pump. Since the oil pump is driven, when the oil level stored in the oil storage means is normal, the pressure pulsation of the oil discharged from the first oil pump is canceled by the second oil pump, and the second The oil pump discharge pressure becomes constant.

Further, when the oil stored in the oil storage means is insufficient, air suction occurs in the first oil pump and the second oil pump, and the pressure of the oil discharged from the first oil pump and the second oil pump Pulsation occurs. This pressure pulsation is vibration caused by the air biting, and the fluctuation range of the pressure pulsation is small and irregular as compared with the case where the oil level is normal.
For this reason, the pressure pulsation of the oil discharged from the second oil pump is generated without the pressure pulsation of the oil discharged from the first oil pump being canceled by the second oil pump.

The abnormality determination device for an internal combustion engine has hydraulic pressure detection means for detecting the pressure of oil discharged from the second oil pump on the downstream side of the second oil pump, and the abnormality determination means detects detection information of the hydraulic pressure detection means. The hydraulic pressure abnormality is determined on the condition that the fluctuation range of the pressure pulsation of the oil discharged from the second oil pump exceeds a predetermined threshold.
For this reason, the abnormality determination means includes a constant hydraulic pressure discharged from the second oil pump when the oil level stored in the oil storage means is normal, and oil discharged from the second oil pump due to air suction. Pressure pulsation can be accurately distinguished. As a result, it is possible to detect at an early stage that the oil stored in the oil storage means is insufficient.

  In the abnormality determination device for an internal combustion engine according to (1), (2) the first supplied part is driven at a constant speed with the first oil pump and the second oil pump and is lubricated by the oil. The second portion to be supplied is configured to include a hydraulic drive component that is driven based on hydraulic pressure.

  In this internal combustion engine, the first supplied part is constituted by a sliding part lubricated by oil, and the second supplied part is constituted by a hydraulic drive part driven based on hydraulic pressure. The high-pressure oil can be supplied from the second oil pump to the hydraulic drive parts without causing an increase in the size of the oil pump 1 even when the internal combustion engine is running at a low speed.

  In addition, since the small amount of oil can be supplied from the first oil pump to the sliding portion when the internal combustion engine is running at a low speed, the sliding resistance of the sliding portion is prevented from increasing and the fuel consumption of the internal combustion engine is deteriorated. Can be prevented.

  In the abnormality determination device for an internal combustion engine according to the above (1) or (2), (3) warning means for giving a warning based on an abnormality signal output from the abnormality determination means, the abnormality determination means includes the first 2 is configured to output the abnormal signal to the warning means on condition that the fluctuation range of the pressure pulsation of oil discharged from the oil pump 2 exceeds a predetermined threshold.

  This abnormality determination device for an internal combustion engine has warning means for giving a warning based on an abnormality signal output from the abnormality determination means, and the abnormality determination means detects fluctuations in pressure pulsations of oil discharged from the second oil pump. Since an abnormal signal is output to the warning means on condition that the width exceeds a predetermined threshold, it is possible to warn the driver that the oil stored in the oil storage means is insufficient. For this reason, it is possible to prompt the driver to check the oil in the oil storage means or to replenish the oil storage means with oil.

  For this reason, oil can be supplied to the sliding portion and the hydraulic drive component at an early stage, and it is possible to avoid the occurrence of seizure of the sliding portion and the deterioration of the behavior of the hydraulic drive component.

  In the internal combustion engine abnormality determination device according to any of (1) to (3), (4) the first oil pump and the second oil pump are driven by an output shaft of the internal combustion engine, and the first The oil pump is configured to shift the phase of the discharge timing of oil discharged from the second oil pump.

  In this internal combustion engine, the first oil pump and the second oil pump are driven by the output shaft of the internal combustion engine, and the phase of the discharge timing of the oil discharged from the first oil pump and the second oil pump is shifted. Thus, the pressure pulsation of the oil discharged from the first oil pump and the pressure pulsation of the oil discharged from the second oil pump can be in opposite phases.

  ADVANTAGE OF THE INVENTION According to this invention, the abnormality determination apparatus of the internal combustion engine which can detect early that it was insufficient for the oil stored by the oil storage means can be provided.

1 is a diagram showing an embodiment of an abnormality determination device for an internal combustion engine according to the present invention, and is a schematic configuration of a vehicle including an abnormality determination device for an internal combustion engine. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an embodiment of an abnormality determination device for an internal combustion engine according to the present invention, and is a block diagram showing each supplied portion of the engine and the flow of oil. It is a figure which shows one Embodiment of the abnormality determination apparatus of the internal combustion engine which concerns on this invention, The phase of the pressure pulsation of the oil discharged from a 1st oil pump, and the pressure pulsation of the oil discharged from a 2nd oil pump FIG. It is a figure which shows one Embodiment of the abnormality determination apparatus of the internal combustion engine which concerns on this invention, and is a flowchart of an abnormality determination process. It is a figure which shows one Embodiment of the abnormality determination apparatus of the internal combustion engine which concerns on this invention, and shows the pressure pulsation of the oil discharged from a 2nd oil pump when the oil level in an oil pan is appropriate, and when it falls FIG.

Embodiments of an abnormality determination device for an internal combustion engine according to the present invention will be described below with reference to the drawings.
1 to 5 are diagrams showing an embodiment of an abnormality determination device for an internal combustion engine according to the present invention.
First, the configuration will be described.
In FIG. 1, a vehicle 1 includes an engine 2 as an internal combustion engine, an oil supply device 3, and an abnormality determination device 4 for the engine 2.

  The engine 2 performs a series of four strokes including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke while a piston 21 accommodated in a cylinder (not shown) so as to be able to reciprocate is reciprocated twice. It is an engine.

  The engine 2 is an in-line four-cylinder engine having four cylinders and four pistons 21 each. The number of cylinders is an example, and is not limited to four cylinders. The engine 2 is not limited to a gasoline engine but may be a diesel engine.

  The engine 2 includes a piston 21, a variable valve timing mechanism (hereinafter referred to as VVT) 22, a crankshaft 23, a cylinder head 27 (see FIG. 3), a cylinder block 28 (see FIG. 3), and a crankcase. And an unillustrated fuel injection device for injecting fuel into the cylinder.

  The VVT 22 is a mechanism that controls the intake valve 25a and the exhaust valve 25b at an optimal opening / closing timing according to the operating state. The VVT 22 includes VVT controllers provided at the axial ends of the intake camshaft 26a and the exhaust camshaft 26b.

  The VVT 22 changes the phase of the intake camshaft 26a and the exhaust camshaft 26b with respect to the cam sprocket by supplying hydraulic pressure to each VVT controller, thereby advancing or retarding the opening / closing timing of the intake valve 25a and the exhaust valve 25b. be able to.

  The hydraulic pressure supplied to each VVT controller of the VVT 22 is controlled by intake side and exhaust side oil control valves (OCV) 22a, 22b.

  The crankshaft 23 is rotatably supported by the engine block 24 via a crank journal 23a. Further, the crankshaft 23 is connected to the piston 21 via a connecting rod 21a, and the reciprocating motion of the piston 21 is transmitted to rotate. The connecting rod 21a is connected to the crankpin 23b of the crankshaft 23.

  As shown in FIGS. 1 and 2, the oil supply device 3 includes an oil pan 30 as oil storage means, an oil strainer 31, oil pumps 32 and 33, an oil filter 34, an oil passage 35, and an oil supply. And a path 36. However, the oil filter 34 is not shown in FIG.

  An oil strainer 31 is immersed in the oil pan 30, and the oil strainer 31 filters oil stored in the oil pan 30.

  The oil stored in the oil pan 30 is sucked up by an oil pump 32 as a first oil pump through an oil strainer 31 and discharged from the oil pump 32 to an oil passage 35.

As shown in FIG. 2, an oil filter 34 is interposed in the oil passage 35, and the oil filter 34 removes foreign matters mixed in the oil.
A main gallery 37 is provided on the downstream side of the oil passage 35, and the main gallery 37 extends in the wall surface of the cylinder block 28 along the crankshaft 23 (see FIG. 1). The main gallery 37 is supplied with oil pressurized by the oil pump 32, and the oil supplied to the main gallery 37 is branched and supplied to the cylinder head 27 and the cylinder block 28. It has become.

In addition, the downstream side said by this Embodiment is a direction through which oil flows. For example, the downstream sides of the oil pumps 32 and 33 are directions on the side from which oil is discharged from the oil pumps 32 and 33, respectively.
The oil branched and supplied to the cylinder head 27 and the cylinder block 28 is supplied to each supply site of the engine 2.

  For example, in the cylinder block 28, the supplied oil is used as lubricating oil for the crank journal 23a, the crank pin 23b, the connecting rod 21a and the like constituting the sliding portion, and as the hydraulic oil for the oil jet 38 constituting the hydraulic drive part. The cylinder head 27 is used as lubricating oil such as a cam journal 29 that rotatably supports the intake camshaft 26a and the exhaust camshaft 26b, and as hydraulic oil for the lash adjuster 50 and the VVT 22 that constitute hydraulically driven parts.

  In the present embodiment, the sliding part constituting the first supplied part is constituted by the crank journal 23a, the crank pin 23b, the connecting rod 21a, and the piston 21 to which oil is supplied from the oil jet 38. The hydraulic drive components such as the lash adjuster 50 and the VVT 22 constitute the second supply target part.

  Here, the oil jet 38 injects oil toward the bottom surface of the piston 21 (see FIG. 1) of the engine 2 to cool the piston 21 that is exposed to the combustion gas and has a high thermal load. It is intended to prevent knocking by preventing abnormal combustion during operation.

  The oil pump 33 as a second oil pump is provided on the downstream side of the oil pump 32 and on the downstream side of the main gallery 37. The oil supplied to the main gallery 37 by the oil pump 32 is supplied to the cam journal. The oil is supplied as lubricating oil such as 29, or as hydraulic oil for the lash adjuster 50 or the VVT 22.

  The oil supplied to each supply site is then dropped inside the engine block 24 and returned to the oil pan 30 again. The oil supply path 36 of the oil supply device 3 is configured to include an oil passage 35 and a main gallery 37, and after supplying the oil stored in the oil pan 30 to each supplied part of the engine 2, the oil pan 30 It is configured as a circulation path for recovery.

  That is, the oil supply path 36 is an oil circulation path from supplying the oil stored in the oil pan 30 to each supply site of the engine 2 by the oil pumps 32 and 33 and then collecting the oil to the oil pan 30.

  The oil pumps 32 and 33 are composed of, for example, an oil pump of the same model including a trochoid pump and a gear pump, and are connected to a crankshaft 23 that is an output shaft of the engine 2 via a chain (not shown). 23 is driven at a constant speed by a crankshaft 23 on a separate axis. The oil pumps 32 and 33 may be driven coaxially with the crankshaft 23 via a chain.

  The oil pumps 32 and 33 are configured so that the pressure pulsation of the oil discharged from the oil pump 33 is in an opposite phase to the pressure pulsation of the oil discharged from the oil pump 32. .

  Specifically, the oil pumps 32 and 33 are configured such that the centers of the inner rotor and the outer rotor are eccentric from each other, and the number of teeth of the inner rotor is one less than the number of teeth of the outer rotor. As a result, the space between the inner rotor and the outer rotor is expanded and contracted to perform a pumping action.

  Since the space defined by one tooth of the inner rotor and one tooth of the outer rotor faces the discharge port in a compressed state, high pressure oil is discharged at the time of discharge, and the next one tooth of the inner rotor And high pressure oil is discharged again when the space defined by the teeth of the outer rotor faces the discharge port. Then, the pressure is low between the discharge of the high pressure oil and the next discharge of the high pressure oil.

For this reason, the pressure fluctuation, that is, the pressure pulsation is generated by alternately repeating the hydraulic pressure to a high pressure and a low pressure as the inner rotor rotates.
Therefore, in this embodiment, the discharge timing of the high-pressure oil discharged from the oil pumps 32 and 33 is shifted by shifting the phases of the teeth of the inner rotor and the teeth of the outer rotor of the oil pumps 32 and 33, respectively. Thus, as shown in FIG. 3, the pressure pulsations P1 and P2 of the oil discharged from the oil pumps 32 and 33 can be in opposite phases.

Further, when shifting the phase between the teeth of the inner rotor and the teeth of the outer rotor of each of the oil pumps 32, 33, the upper limit value of the pressure pulsation of the oil discharged from the oil pump 32 and the oil discharged from the oil pump 33 The timing at which the lower limit value of the pressure pulsation coincides with the timing at which the lower limit value of the pressure pulsation of oil discharged from the oil pump 32 and the upper limit value of the pressure pulsation of oil discharged from the oil pump 33 match. To do.
As a result, the pressure pulsation of the oil discharged from the oil pump 32 is canceled by the oil pump 33, and the pressure of the oil discharged from the oil pump 33, that is, the hydraulic pressure P3 becomes a flat hydraulic pressure with the pressure pulsation canceled. .

  On the other hand, the abnormality determination device 4 includes an electronic control unit (hereinafter referred to as ECU) 41, a hydraulic pressure sensor 42 as hydraulic pressure detection means, and a warning lamp 43.

  The oil pressure sensor 42 is provided on the oil supply path 36 on the discharge side of the oil pump 33. The oil pressure sensor 42 detects the pressure of the oil discharged from the oil pump 33 and sends a signal corresponding to the oil pressure to the ECU 41. To output.

The ECU 41 includes, for example, a microcomputer including a CPU, a RAM, a ROM, an input / output interface, and the like.
In the ROM, a control program such as an abnormality determination program described later, initial data, various control maps, and the like are stored in advance.

  The CPU uses the temporary storage function of the RAM and performs arithmetic processing according to the abnormality determination program, initial data and various control maps stored in advance in the ROM, and executes various controls such as abnormality determination processing based on the calculation results. It is supposed to be. The RAM temporarily stores data and functions as a work area.

  Based on the detection information of the hydraulic sensor 42, the ECU 41 determines that the hydraulic pressure is abnormal on the condition that the fluctuation range of the pressure pulsation of the oil discharged from the oil pump 33 exceeds a predetermined threshold (for example, 50 kPa). It constitutes an abnormality determination means.

  When the ECU 41 determines that the hydraulic pressure is abnormal, the ECU 41 determines that the oil level in the oil pan 30 has decreased and the oil supplied to each supply portion of the engine 2 is insufficient, and notifies the warning lamp 43 of an abnormality signal. Is output.

  The warning lamp 43 lights or blinks when an abnormal signal is input from the ECU 41, and warns the driver that the oil in the oil pan 30 is insufficient. In the abnormality determination device 4 of the present embodiment, the warning lamp 43 constitutes a warning means.

  The driver can recognize that the oil level in the oil pan 30 has dropped by looking at the state of the warning lamp 43, and the warning lamp 43 can check the oil in the oil pan 30 or The operation of replenishing the oil pan 30 with oil can be promoted.

  The abnormality determination device 4 may issue a warning by a warning sound by a buzzer or a sound output from a speaker, instead of lighting or blinking the warning lamp 43, as a warning that a hydraulic pressure abnormality has occurred.

Next, an abnormality determination process executed by the ECU 41 of the abnormality determination device 4 for the internal combustion engine will be described with reference to FIGS.
FIG. 4 is a flowchart of the abnormality determination process executed by the ECU 41, and the CPU of the ECU 41 executes an abnormality determination program stored in the ROM.

  The CPU of the ECU 41 determines whether or not the fluctuation range PS of the pressure pulsation of the oil discharged from the oil pump 33 exceeds a predetermined threshold value P0 based on the detection information of the hydraulic pressure sensor 42 (step S1). If it is determined that the pressure does not exceed P0, it is determined that the oil level in the oil pan 30 is appropriate and the oil pressure discharged from the oil pump 33 is normal, and the current process is performed. finish.

  That is, when the oil level of the oil pan 30 is appropriate, the oil sucked up by the oil pump 32 from the oil pan 30 passes through the main gallery 37 from the oil passage 35 to the crank journal 23a, the crank pin 23b, the connecting rod 21a, the oil It is supplied to the jet 38.

  Further, oil discharged from the oil pump 32 is supplied to the hydraulic drive parts such as the VVT 22 and the lash adjuster 50 and the cam journal 29 by the oil pump 33 on the oil supply path 36 branched from the main gallery 37.

  The oil pumps 32 and 33 of the oil supply device 3 of the present embodiment are driven so that the pressure pulsation of the oil discharged from the oil pump 33 is in reverse phase with respect to the pressure pulsation of the oil discharged from the oil pump 32. It is configured to be.

  Therefore, the pressure pulsation of the oil discharged from the oil pump 32 can be canceled by the oil pump 33, and the pressure of the oil discharged from the oil pump 33 is canceled as shown in FIG. The oil pressure becomes flat and the pressure pulsation is less than the threshold value P0.

  If the CPU of the ECU 41 determines in step S1 that the fluctuation range PS of the pressure pulsation of the oil discharged from the oil pump 33 exceeds a predetermined threshold value P0, an abnormal signal is sent to the warning lamp 43. This is transmitted (step S2), and the current process is terminated.

That is, when the oil level in the oil pan 30 is lowered, the oil pump 32 is in an air sucking state, and the oil pump 32 bites bubbles, so-called air biting occurs. When the oil pump 32 causes the air to bite, the vibration generated when the oil pump 32 bites the bubbles becomes pressure pulsation.
Since this pressure pulsation is the entrapment of bubbles when the amount of oil sucked into the oil pump 32 is small, the fluctuation range is smaller than the pressure pulsation when the oil level is normal. Further, this pressure pulsation becomes an irregular pressure pulsation under the influence of the air bite.

  In addition, when the oil discharged from the oil pump 32 is sucked up by the oil pump 33, the oil pump 33 also causes air biting. For this reason, the pressure pulsations of the oil discharged from the oil pumps 32 and 33 are both irregular due to the influence of the air bite, and the oil pump 33 cannot cancel the pressure pulsations.

  Therefore, as shown in FIG. 5, the pressure pulsation PS of the oil discharged from the oil pump 33 is generated. When the CPU of the ECU 41 determines that the fluctuation range PS of the pressure pulsation is equal to or greater than the threshold value P0, the CPU determines that the oil level in the oil pan 30 has decreased and transmits an abnormal signal to the warning lamp 43. .

  The warning lamp 43 illuminates or flashes when an abnormal signal is input from the ECU 41 to warn the driver that the oil level in the oil pan 30 has decreased.

  As described above, in the present embodiment, the oil pumps 32 and 33 are driven so that the pressure pulsation of the oil discharged from the oil pump 33 is in reverse phase with respect to the pressure pulsation of the oil discharged from the oil pump 32. When the oil level stored in the oil pan 30 is normal, the pressure pulsation of the oil discharged from the oil pump 32 can be canceled by the oil pump 33 to make the discharge pressure of the oil pump 33 constant. .

  Under this premise, the ECU 41 of the present embodiment determines that the oil pressure is abnormal on the condition that the fluctuation range PS of the pressure pulsation of the oil discharged from the oil pump 33 exceeds a predetermined threshold value P0. Accurate hydraulic pressure discharged from the oil pump 33 when the oil level in the pan 30 is normal and pressure pulsation of oil discharged from the oil pump 33 when the oil level in the oil pan 30 is reduced. Can be distinguished. As a result, it is possible to detect at an early stage that the oil stored in the oil pan 30 is insufficient.

In particular, in the oil supply device 3 of the present embodiment, when the oil level in the oil pan 30 is appropriate, the oil pressure discharged from the oil pump 33 has a flat characteristic. Thus, the threshold value P0 can be reduced, and even when the pressure pulsation is small, it can be immediately determined that the oil level in the oil pan 30 has decreased.
Therefore, it is possible to detect earlier that the oil level in the oil pan 30 has decreased. That is, the abnormality determination device 4 of the present embodiment can increase the sensitivity for detecting a hydraulic pressure abnormality.

  Further, in the engine 2 of the present embodiment, the first supplied portion is driven at a constant speed with the oil pump 33 and the oil pump 33, and is lubricated with oil by a crank journal 23a, a crank pin 23b, a connecting rod 21a, The second portion to be supplied is configured to include hydraulic drive parts such as the VVT 22 and the lash adjuster 50 that are driven based on the hydraulic pressure.

  For this reason, high-pressure oil can be supplied from the oil pump 33 to the VVT 22 and the lash adjuster 50 even when the engine 2 is rotating at low speed without causing an increase in the size of the oil pump 32.

Further, since a small amount of oil can be supplied from the oil pump 32 to the sliding portion when the engine 2 is running at a low speed, the sliding resistance of the sliding portion is prevented from increasing and the fuel consumption of the engine 2 is deteriorated. Can be prevented.
In particular, the oil supply device 3 of the present embodiment has a flat characteristic in which there is no upper limit hydraulic pressure and no lower limit hydraulic pressure of the oil pressure pulsation discharged from the oil pump 33. The discharge pressure can be increased.

For this reason, for example, the hydraulic pressure supplied to the VVT 22 can be increased, and the reliability of the VVT 22 can be improved.
Specifically, in the conventional oil pump that generates pressure pulsation when the oil level is appropriate, in order to operate the VVT 22 stably, it is preferable to set the operating oil pressure of the VVT 22 to the lower limit oil pressure. Is set to the lower limit hydraulic pressure, it is necessary to increase the pressure of the oil supplied to the VVT 22 by increasing the size of the oil pump.

  On the other hand, since the oil pump 33 according to the present embodiment has a flat characteristic, the lower limit hydraulic pressure can be substantially increased to a flat hydraulic pressure, and the operating hydraulic pressure of the VVT 22 is increased to increase the reliability of the VVT 22. Can be improved.

  In addition, the abnormality determination device 4 of the present embodiment has a warning lamp 43 that issues a warning based on an abnormality signal output from the ECU 41, and the ECU 41 changes the fluctuation range of the pressure pulsation of oil discharged from the oil pump 33. An abnormality signal is output to the warning lamp 43 to the warning means on condition that PS exceeds a predetermined threshold value P0.

  For this reason, it is possible to warn the driver that the oil in the oil pan 30 is insufficient, and urge the driver to check the oil in the oil pan 30 or to replenish the oil in the oil pan 30. be able to.

  For this reason, oil can be supplied to the sliding portion and the hydraulic drive component at an early stage, and it is possible to avoid the occurrence of seizure of the sliding portion and the deterioration of the behavior of the hydraulic drive component.

  In the present embodiment, the oil pumps 32 and 33 are driven by the crankshaft 23 of the engine 2 so that the phase of the discharge timing of the oil discharged from the oil pumps 32 and 33 is shifted. The pressure pulsation of the oil discharged from 32 and the pressure pulsation of the oil discharged from the oil pump 33 can be in opposite phases.

  The abnormality determination device 4 for an internal combustion engine according to the present embodiment has been described with reference to an example applied to an internal combustion engine for a vehicle. However, any device using an internal combustion engine as a power source can be applied. The present invention can be applied not only to an internal combustion engine mounted on a motorcycle or a motorcycle but also to an internal combustion engine mounted on a vehicle other than a vehicle such as a ship or a construction machine.

  As described above, the abnormality determination device for an internal combustion engine according to the present invention has an effect that it can be detected at an early stage that the oil stored in the oil storage means is insufficient, and is caused by a decrease in the oil level. This is useful as an abnormality determination device for an internal combustion engine that determines an abnormality in hydraulic pressure.

2 Engine (Internal combustion engine)
4 Abnormality determination device 21 Piston (first supplied part, sliding part)
21a Connecting rod (first supplied part, sliding part)
22 VVT (second supply part, hydraulic drive part)
23a Crank journal (first supplied part, sliding part)
23b Crank pin (first supplied part, sliding part)
30 Oil pan (oil storage means)
32 Oil pump (first oil pump)
33 Oil pump (second oil pump)
38 Oil jet (first supplied part, sliding part)
41 ECU (abnormality determination means)
42 Hydraulic sensor (hydraulic detection means)
43 Warning lamp (Warning means)
50 Rush adjuster (second supply part, hydraulically driven parts)

Claims (4)

A first oil pump that supplies oil stored in the oil storage means to the first supplied part, and provided at a downstream side with respect to the first oil pump, and at a constant speed with respect to the first oil pump. And a second oil pump that supplies oil supplied from the first oil pump to the second supply site, and the pressure pulsation of oil discharged from the first oil pump. An abnormality determination device provided in an internal combustion engine in which the first oil pump and the second oil pump are driven so that pressure pulsations of oil discharged from a second oil pump are in reverse phase,
A hydraulic pressure detecting means provided on the downstream side of the second oil pump for detecting the pressure of oil discharged from the second oil pump;
Based on detection information of the oil pressure detection means, an abnormality determination means that determines that the oil pressure is abnormal on the condition that the fluctuation range of the pressure pulsation of the oil discharged from the second oil pump exceeds a predetermined threshold value An abnormality determination device for an internal combustion engine, comprising: The first supplied part is composed of a sliding part that is driven at a constant speed with the first oil pump and the second oil pump and is lubricated by the oil;
The abnormality determination device for an internal combustion engine according to claim 1, wherein the second supplied part includes a hydraulic drive component driven based on hydraulic pressure. Warning means for giving a warning based on an abnormality signal output from the abnormality determination means;
The abnormality determination means outputs the abnormality signal to the warning means on condition that the fluctuation range of the pressure pulsation of oil discharged from the second oil pump exceeds a predetermined threshold value. The abnormality determination device for an internal combustion engine according to claim 1 or 2.   The first oil pump and the second oil pump are driven by the output shaft of the internal combustion engine, and the phase of the discharge timing of oil discharged from the first oil pump and the second oil pump is shifted. The abnormality determination device for an internal combustion engine according to any one of claims 1 to 3, characterized in that:

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