WO2012176736A1

WO2012176736A1 - Internal combustion engine, and method of controlling same

Info

Publication number: WO2012176736A1
Application number: PCT/JP2012/065513
Authority: WO
Inventors: 小松　明
Original assignee: いすゞ自動車株式会社
Priority date: 2011-06-24
Filing date: 2012-06-18
Publication date: 2012-12-27
Also published as: JP5887727B2; JP2013007318A

Abstract

An internal combustion engine (10) is provided with a control apparatus (40) for controlling a variable oil pump (20) and an auxiliary brake system (30). The amount of engine oil supplied by the variable oil pump (20) is increased when the internal combustion engine (10) is operating in: a high load state; a state in which the actual fuel injection amount (Qm)(or the instructed fuel injection amount (Qt)) is zero during deceleration; and a state in which the actual fuel injection amount (Qm)(or the instructed fuel injection amount (Qt)) is zero when an auxiliary brake is activated. Thus, in the high load state, which requires a large supply amount of engine oil, lubrication and cooling can be performed with a sufficient amount of engine oil, and in the state in which the auxiliary brake is activated, the energy of an engine drive shaft (12) can be recovered for driving the variable oil pump (20) when fuel is definitely not being injected, so that the supply amount of engine oil can be increased without worsening of fuel efficiency, and the required braking force can be efficiently obtained.

Description

Internal combustion engine and control method thereof

The present invention relates to an internal combustion engine and a control method therefor, and more specifically, in an internal combustion engine such as an automobile engine or an industrial engine, in a high load state, the supply amount of engine oil is increased so that a necessary and sufficient amount of engine is provided. Lubricating and cooling can be performed efficiently with oil, and in the operating state of the auxiliary brake, the required amount of braking force can be efficiently obtained by increasing the supply amount of engine oil while avoiding deterioration of fuel consumption. The present invention relates to an internal combustion engine including a variable oil pump and a control method thereof.

Recent exhaust gas regulations for automobile engines and industrial engines that use internal combustion engines are becoming stricter year by year. In addition to this, strict fuel efficiency regulations have been introduced in recent years as a global warming countermeasure. In order to meet these demands, the latest engines simultaneously perform research and development for improving fuel efficiency by improving combustion, as well as research and development for improving fuel efficiency by reducing friction of the engine body, which is an internal combustion engine. It has been broken. However, since the improvement in combustion efficiency in the engine body as an improvement in fuel consumption of the internal combustion engine has reached a limit, research and development for reducing friction in the engine body has recently been activated.

One of the new technologies related to this is to increase the output of the engine with a small displacement, aiming to reduce fuel consumption by using a small engine with small engine friction instead of a large engine with large friction. There is so-called downsizing. For example, fuel consumption can be improved by increasing the output of the conventional full load performance curve shown by the dotted line in FIG. 5 so as to be a performance curve shown by the solid line above it.

This downsizing of the engine increases the engine load compared to the conventional engine, so it is necessary to increase the amount of engine oil supplied to the piston, crank bearing, and the like.

On the other hand, it is necessary to increase the supply amount of engine oil due to the problem of a reduction in braking force due to downsizing the engine. In other words, in commercial vehicles carrying cargo that is equal to or greater than the vehicle weight, the engine braking force decreases due to downsizing of the engine, and the braking force is insufficient only with a normal foot brake, so exhaust brakes, retarders, etc. Auxiliary brakes need to be provided, and new auxiliary brake systems to compensate for this have become necessary.

As one of the new auxiliary brake systems, a hydraulically operated valve is attached to the exhaust valve of the engine, and this valve is operated during the compression stroke of the engine to release the compressed gas of the engine and greatly reduce the engine energy. A compression-type open brake system that converts energy into energy has been developed. In this compression-type release brake system, high pressure hydraulic pressure is required to operate this valve, and the supply amount of engine oil needs to be increased.

In this connection, as described in Japanese Patent Application Laid-Open No. 2001-152822, for example, the engine stop that opens the exhaust valve to release the in-cylinder compression pressure at the time of idling stop and at the subsequent restart. An engine brake device has been proposed that opens an exhaust valve using an auxiliary hydraulic unit (comprising a pressure accumulator) that includes an hourly valve opening means and communicates with an oil pump of the engine. Further, for example, as described in Japanese Patent Application Laid-Open No. 11-223114, the exhaust valve is opened by a compression stroke independently of the normal valve timing by the hydraulic pressure in the pressure accumulating chamber by engine lubricating oil. An engine brake device has been proposed.

If the engine oil pump is increased in size in order to satisfy the demand for increasing the amount of engine oil supplied, there is a problem that the engine friction increases due to the increase in size and the fuel consumption of the engine deteriorates.

On the other hand, with oil pumps as well, focusing on the fact that conventional pumps are wasteful and are not the optimum pump work required by the engine, attention has been focused on improving fuel efficiency by changing oil pumps. Normally, this oil pump is connected to an engine drive unit by a gear or a belt, and is rotationally driven by directly transmitting the output of the engine. Therefore, generally, the rotation speed of the oil pump is proportional to the engine rotation speed. The specifications and flow rate of the oil pump are selected based on the severest engine full load operation conditions in engine operation.

However, engine oil should be supplied according to the need for lubrication of each part of the engine and cooling of the piston, etc., and the optimum flow rate of engine oil required on the engine side is not necessarily proportional to the engine speed, It is best that the flow rate is adjusted to the optimum according to the engine operating state (engine speed, engine load). Therefore, the current oil pump driving method does a useless work depending on engine operating conditions. Therefore, various variable oil pumps have been developed in order to make it possible to change the supply amount of engine oil with the aim of improving fuel efficiency by reducing this useless work amount.

In addition, the demand for the supply amount of engine oil in this variable oil pump has become very complex due to the influence of each device attached to the engine, and the oil pump mechanically increases as the engine speed increases. In the control of the oil pump that controls to increase the pressure of the supplied engine oil, it is difficult to respond to these fine control requirements of the oil pump.

As described above, in an internal combustion engine, in order to improve fuel efficiency, a variable oil pump is adopted to control the engine oil supply amount to be optimal. There is a problem in that it is technically very difficult to supply engine oil at an optimum supply amount that meets this demand, since a supply amount for realizing the corresponding hydraulic pressure is required.

In this connection, for example, as described in Japanese Patent Application Laid-Open No. 10-318158, a part of hydraulic oil discharged from an oil pump that is rotationally driven by a drive source such as an engine is recirculated. As a control valve, a sub port, a main port, and a control port are provided, and the combination enables the oil pump to operate in the first to fourth control modes, thereby reducing the size and weight of the oil pump device and reducing the pump load. Oil pump devices have been proposed to maximize this. However, this oil pump device has a problem that the structure and the control are complicated.

Further, for example, as described in Japanese Patent Application Laid-Open No. 2005-114103, the amount of hydraulic oil discharged from the oil pump to the continuously variable transmission is switched depending on the driving state of the vehicle, thereby improving the fuel consumption performance. An oil pump control device that keeps good is proposed. In some cases, such as when the engine is running slowly, when the vehicle is stopped, or when the brakes are operated, the hydraulic oil discharged from the oil pump is switched by the switching valve. The oil circulation is reduced to about half of that during low-speed operation. This oil pump control device only reduces the amount of hydraulic oil when the engine is operating with low engine output and low lubrication, and does not recover energy from the engine drive shaft. There is a problem that improvement is limited.

In other words, in order to improve the fuel efficiency of an engine that is a recent internal combustion engine, it is necessary to reduce the engine friction as much as possible. Therefore, the development of a variable oil pump system that can supply optimal oil However, due to higher engine output, higher engine oil flow is required when the engine is in a heavy load state. On the other hand, higher engine oil pressure is required to supply an auxiliary brake system that enhances vehicle braking force. The contents required for oil pumps are diversified.

On the other hand, simply increasing the size of the oil pump simply in accordance with the demand for an increase in the supply amount will cause the fuel consumption of the engine to deteriorate. As a means to improve these, proposals of variable oil pumps have been submitted but are insufficient.

Japanese Patent Application No. 2001-152822 Japanese Patent Application No. 11-223114 Japanese Patent Application No. 10-318158 Japanese Patent Application No. 2005-114103

The present invention has a demand for reducing the friction of the internal combustion engine as much as possible on the one hand as described above. On the other hand, the downsized engine has a high load state that requires lubrication and cooling with engine oil. To increase the engine oil supply, there is a need for the operation of an auxiliary brake system to enhance vehicle braking force in order to generate and for engine brake shortage in a downsized engine It was made in view of the situation.

An object of the present invention is to increase the supply amount of engine oil when the operating state of the internal combustion engine is a high load state where a large amount of engine oil needs to be supplied, and perform lubrication and cooling with a sufficient amount of engine oil. In addition, when the auxiliary brake is in operation, the energy of the engine drive shaft is recovered and the variable oil pump is driven in a state where fuel is not reliably injected, thereby avoiding deterioration in fuel consumption. An object of the present invention is to provide an internal combustion engine and a control method therefor that can increase the amount of engine oil supplied, increase the auxiliary braking force, and efficiently obtain the necessary braking force.

In other words, an object of the present invention is to provide a variable oil pump according to the state of various engines and vehicles, with respect to the increase or decrease in the amount of engine oil supply required according to the situation from various engines, drivers and vehicles. It is an object of the present invention to provide an internal combustion engine and a control method therefor that can improve the fuel efficiency of the engine by controlling the output of the engine.

In order to achieve the above object, an internal combustion engine of the present invention includes a variable oil pump capable of changing the supply amount of engine oil with respect to the engine speed of the internal combustion engine, and an engine oil supplied from the variable oil pump. An internal combustion engine comprising: an auxiliary brake system that uses an engine; and an operation state detection unit that detects an operation state of the internal combustion engine, and the control device that controls the variable oil pump and the auxiliary brake system. When the operating state of the internal combustion engine detected by the operating state detecting means is a high load state, when the actual fuel injection amount or the commanded fuel injection amount is zero in the deceleration state, and when the auxiliary brake is operating, When the fuel injection amount or the command fuel injection amount is zero, the engine oil supply amount by the variable oil pump is increased. Configured to perform control.

According to this configuration, when the operating state of the internal combustion engine is in a high load state where a large amount of engine oil needs to be supplied, the amount of engine oil supplied is increased, and lubrication and cooling are efficiently performed with a necessary and sufficient amount of engine oil. It can be carried out.

Further, in order to accurately detect the deceleration state and the braking state of the vehicle in the operation state of the auxiliary brake, the actual fuel injection amount actually injected from the control device to the engine or the instructed fuel injection amount actually instructed By further using the determination that is zero, it is possible to recover the rotational energy of the engine drive shaft and drive the variable oil pump in a state where fuel is not reliably injected. As a result, the amount of engine oil supplied by the variable oil pump can be increased, so that an increase in fuel consumption for this increase can be avoided. Accordingly, the engine oil can be supplied to the auxiliary brake system while increasing its supply amount while avoiding deterioration of fuel consumption, and the necessary braking force can be obtained efficiently.

The operation state of the auxiliary brake can be determined by determining whether or not all of the auxiliary brake operation switch is ON, the accelerator switch is OFF, the clutch switch is OFF, and the transmission neutral switch is OFF. it can. The increase in the supply amount of the variable oil pump depends on the configuration of the variable oil pump, but the second oil is changed by changing the gear ratio between the variable oil pump and the engine drive shaft and turning on the electromagnetic clutch provided in the variable pump. This can be done by operating the pump.

In the internal combustion engine provided with the variable oil pump described above, the auxiliary brake system is configured to be a compression type open brake system in which an exhaust valve of a cylinder of the internal combustion engine is provided with a hydraulically operated valve. When this configuration is adopted, the necessary braking force can be obtained efficiently while avoiding deterioration of fuel consumption in the compression-type open brake system.

And the control method of the internal combustion engine of the present invention for achieving the above object includes a variable oil pump capable of changing the supply amount of engine oil with respect to the engine speed of the internal combustion engine, and the variable oil pump. Control of an internal combustion engine comprising an auxiliary brake system using engine oil supplied and an operation state detection means for detecting an operation state of the engine and the control unit for controlling the variable oil pump and the auxiliary brake system In the method, when the operation state of the internal combustion engine detected by the operation state detection means is a high load state, when the actual fuel injection amount or the command fuel injection amount is zero in the deceleration state, and the operation state of the auxiliary brake When the actual fuel injection amount or the indicated fuel injection amount is zero, supply of engine oil by the variable oil pump A method characterized by increasing the amount of.

According to this method, when the operating state of the internal combustion engine is in a high load state where a large amount of engine oil needs to be supplied, the amount of engine oil supplied is increased, and lubrication and cooling are efficiently performed with a sufficient amount of engine oil. It can be carried out. Further, by using the determination that the actual fuel injection amount or the command fuel injection amount is zero in the operation state of the auxiliary brake, it is possible to avoid fuel consumption for increasing the supply amount of engine oil, The energy of the drive shaft can be efficiently recovered, the auxiliary brake force can be increased, and the necessary braking force can be obtained efficiently.

According to the internal combustion engine and the control method thereof according to the present invention, when the operating state of the internal combustion engine is a high load state where a large amount of engine oil needs to be supplied, the supply amount of the engine oil is increased and a necessary and sufficient amount of engine is increased. Oil lubrication and cooling can be performed efficiently, and when the auxiliary brake is in operation, the variable oil pump is driven by recovering the energy of the engine drive shaft without fuel being reliably injected. While avoiding deterioration, the supply amount of engine oil can be increased, the auxiliary brake force can be increased, and the necessary braking force can be efficiently obtained.

In particular, in the present invention, the actual fuel injection amount actually detected or the command fuel injection amount actually instructed to the engine from the control device for the control to accurately detect the deceleration and the braking state of the vehicle. As a result, it is possible to perform control to increase the supply amount of the variable oil pump by grasping the braking state of the vehicle in which fuel is not reliably injected and the braking state. And the variable oil pump can be controlled efficiently.

FIG. 1 is a diagram showing a configuration related to a variable oil pump of an internal combustion engine according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of a control flow of the variable oil pump. FIG. 3 is a diagram showing an example of a high load basic operation map for the variable oil pump. FIG. 4 is a diagram illustrating an example of an auxiliary brake basic operation map for the variable oil pump. FIG. 5 is a diagram showing the relationship between the engine speed of the internal combustion engine, the engine output, and the basic operating region of the variable oil pump.

Hereinafter, an internal combustion engine and a control method thereof according to embodiments of the present invention will be described with reference to the drawings. Here, a general manual transmission with a clutch will be described. However, in an automatic transmission, an automatic transmission (smoother), and the like, the type of sensor to be attached may vary depending on individual vehicles, but the present invention is applicable. it can. The present invention can be applied not only to a diesel engine mounted on a vehicle but also to other internal combustion engines such as other engines mounted on a vehicle, industrial engines, and power generation engines.

As shown in FIG. 1, an internal combustion engine according to an embodiment of the present invention is an internal combustion engine (engine) 10 including a variable oil pump 20, and the internal combustion engine 10 includes a variable oil pump 20 and the variable oil. A control device 40 for controlling the variable oil pump 20 and the auxiliary brake system 30 having an auxiliary brake system 30 that uses engine oil supplied from the pump 20 and an operating state detecting means 41 that detects the operating state of the internal combustion engine 10. And is configured. *

The variable oil pump 20 obtains driving force from a gear train 13 of an engine drive shaft 12 provided in the engine body 11 and can change the supply amount of engine oil with respect to the engine rotational speed Ne of the internal combustion engine 10. Configured to be able to. That is, the variable oil pump 20 is not an oil pump in which the supply amount of the engine oil cannot be changed in proportion to the engine speed Ne of the internal combustion engine 10, but the engine oil supply to the same engine speed Ne. It is composed of an oil pump that can change the amount.

For example, the variable oil pump 20 is composed of two pumps, a first oil pump (main oil pump) 21 and a second oil pump (secondary oil pump) 22, and the electromagnetic clutch 23 is turned off. When the second oil pump 22 is not operated, only the first oil pump 21 is operated, engine oil is supplied at a predetermined flow rate, and the electromagnetic clutch 23 is turned on, the first oil pump 21 is operated. In addition, an oil pump configured to increase the flow rate of the engine oil by operating the second oil pump 22 can also be used.

The auxiliary brake system 30 is a system that uses engine oil supplied from the variable oil pump 20, for example, engine oil supplied to the exhaust valve of the internal combustion engine 10 from the variable oil pump 20 via the electromagnetic valve 31. It can be formed by a compression type release brake system provided with a valve 32 (exhaust valve operation valve) that is operated by hydraulic pressure. In this compression-type release brake system, this valve 32 is operated during the compression stroke of the piston of the internal combustion engine 10 to release the compressed gas in the cylinder, and the energy of the internal combustion engine 10 is converted into a large braking energy, whereby the auxiliary brake As a role.

Further, the control device 40 includes an operation state detection unit 41 that detects the operation state of the internal combustion engine 10, and controls the variable oil pump 20 and the auxiliary brake system 30 based on data detected by the operation state detection unit 41. Configured.

The operating state detection means 41 detects the engine speed Ne with the engine speed sensor 14 and detects the actual fuel injection quantity Qm with the fuel injection quantity sensor 15. In relation to the determination of the operation state of the auxiliary brake, the auxiliary brake operation switch 51 of the driver's seat of the vehicle 50 equipped with the internal combustion engine 10 is turned ON / OFF, the accelerator switch 52 is turned ON / OFF, and the clutch switch 53 is turned ON. -OFF, configured to detect ON-OFF of the neutral switch 54 of the transmission.

That is, the auxiliary brake system 30 configured by this compression-type release brake system basically increases the braking force of the vehicle 50 by increasing the friction of the internal combustion engine 10 and increasing the engine braking force. It is. Therefore, it is necessary that the vehicle 50 is not in an accelerating state and that the engine braking force can be effectively operated on the vehicle 50. That is, it is necessary that the tire of the vehicle 50 and the crankshaft of the engine are connected. That is, the engine brake does not operate when the clutch is in an activated state or the transmission is in a neutral state or the like. Therefore, it is necessary to use the auxiliary brake after detecting that it is not in these states and grasping it.

Next, a control method for an internal combustion engine according to an embodiment of the present invention will be described. This control method is a control method implemented by the control apparatus 40, and is implemented by the control flow as shown in FIG.

The control flow of FIG. 2 starts when the engine starts and when called from the advanced control flow, executes step S11 to step S19 or step S11 to step S20, returns to the advanced flow, and ends the engine operation. Until it is repeatedly called from the advanced flow, it has been shown to return. Note that the ON-OFF operation of the second oil pump 22 has been described using the electromagnetic clutch 23 that is electrically operated. However, control and operation for other mechanically operated clutches are also possible. The effect is the same.

When the control flow of FIG. 2 starts, the engine speed Ne and the engine load L are input in step S11. The engine load L is calculated from an accelerator opening degree Ac detected by an accelerator opening degree sensor (not shown). In the next step S12, the fuel injection amount Qc is calculated from the engine speed Ne and the engine load L.

In the next step S13, the operation index P of the variable oil pump 20 is referred to based on the engine speed Ne and the fuel injection amount Qc with reference to the high load basic operation map for the variable oil pump as shown in FIG. Is calculated.

In FIG. 3, “0” or “1” is shown in a table format for the operation index P of the variable oil pump 20 with respect to the engine speed Ne in the horizontal direction and the fuel injection amount Q in the vertical direction. The operation index P of “0” means that the electromagnetic clutch 23 is turned off, only the first oil pump 21 is operated, and the second oil pump 22 is stopped. The operation index P of “1” is This means that the electromagnetic clutch 23 is turned ON, and in addition to the operation of the first oil pump 21, the second oil pump 22 is also operated.

In FIG. 3, the engine speed Ne is 1000 rpm or more, and the fuel injection amount Q is “1” in a high load state of 80 mm ³ / st or more, and “0” in the other operating states of the internal combustion engine 10. FIG. 3 shows a “full load output UP” (shaded portion) where the engine oil becomes insufficient due to the increase in torque due to the high engine output in the upper part of FIG. 5 showing the basic operation region. Indicates that additional operations will be performed. In addition, the high load basic operation map for the variable oil pump as shown in FIG. 3 is obtained by conducting a performance test in advance on an engine test bench and investigating in advance the engine region where the engine oil needs to be increased. Created.

In the next step S14, it is determined whether the operation index P calculated in step S13 is “0” or “1”. If the operation index P is “1” in this determination (YES), the process goes to step S19, the electromagnetic clutch 23 is turned on, the second oil pump 22 is operated for a predetermined time, and the process returns. The predetermined time is a time related to the operation index determination interval in steps S14 and S16, the deceleration state determination interval in step S17, and the actual fuel injection amount determination interval in step S18, and is set in advance. . After the return, it will be called again by the advanced flow and will start.

If the operation index P is “0” in the determination of step S14 (NO), the process goes to step S15, and based on the engine speed Ne and the fuel injection amount Qc, the auxiliary for the variable oil pump as shown in FIG. The operation index P of the variable oil pump 20 is calculated with reference to the brake basic operation map. In FIG. 4, regardless of the engine speed Ne, the fuel injection amount Q is “1” at 0 mm ³ / st, and is “0” in other operating states of the internal combustion engine 10. FIG. 4 shows that the second oil pump 22 is additionally operated in the “auxiliary brake operation” (shaded portion) that requires engine oil by the lower auxiliary brake operation in FIG. 5 showing the basic operation region. ing.

It should be noted that the auxiliary brake basic operation map for the variable oil pump as shown in FIG. 4 is created by setting an area where the fuel injection amount Q of the engine in which the engine brake is used is zero.

In the next step S16, it is determined whether the operation index P calculated in step S15 is “0” or “1”. If the operation index P is “1” in this determination (YES), the process goes to step S17 to determine whether the vehicle is in a deceleration state or an auxiliary brake operation state.

The determination as to whether or not the vehicle is in the deceleration state in step S17 is made based on whether or not the fuel injection amount Qc calculated in step S12 is zero. The auxiliary brake operating state is determined when the auxiliary brake operating switch 51 is ON, the accelerator switch 52 is OFF, the clutch switch 53 is OFF, and the transmission neutral switch 54 is OFF. It is determined that it is in a state.

When the driver intends to use the auxiliary brake system 30 at the time of vehicle deceleration or vehicle braking, the driver himself turns on the auxiliary brake operation switch 51 to turn on the auxiliary brake system 51. 30 is operable. Even if the auxiliary brake operation switch 51 is turned on, the auxiliary brake system 30 does not operate unless all of the following conditions for operating the auxiliary brake system 30 are satisfied.

The accelerator switch 52 is used as one piece of information for operating the auxiliary brake system 30 to determine the driver's intention of accelerating the vehicle or decelerating or stopping the vehicle. The auxiliary brake system 30 does not operate unless the driver removes his / her foot from the accelerator pedal and the accelerator switch 52 is turned off.

The clutch switch 53 and the transmission neutral switch 54 are the same as the accelerator switch 52, and the auxiliary brake system 30 is activated only when the driver removes his / her foot from the clutch pedal and the clutch switch 53 is not turned off. First, the auxiliary brake system 30 is configured not to operate unless the driver turns off the neutral switch 54 of the transmission.

In other words, the driver confirms the intention to operate the auxiliary brake system 30 when the auxiliary brake operation switch 51 is turned ON, and the auxiliary brake is turned OFF when the accelerator switch 52 is turned OFF, the clutch switch 53 is turned OFF, and the transmission neutral switch 54 is turned OFF. Make sure that the system 30 is ready for operation. That is, the auxiliary brake system 30 is configured not to operate in a state where the engine brake is not effective.

If it is determined in step S17 that the vehicle is decelerating or the auxiliary brake is operating (YES), the process goes to step S18 and the actual fuel injection amount Qm detected by the fuel injection amount sensor 15 (or the fuel injection device from the control device 40). It is determined whether or not the command fuel injection amount Qt) that is the command amount to zero is zero (Qm = 0 or Qt = 0). In this determination, if the actual fuel injection amount Qm (or the commanded fuel injection amount Qt) is zero (Qm = 0, Qt = 0: YES), the process goes to step S19 to turn on the electromagnetic clutch 23 to turn on the second oil pump. Operate 22 for a predetermined time and return. This predetermined time is a time related to the determination interval of the operation index in step S14 or S16, the determination interval of the deceleration state or the auxiliary brake operation state in step S17, or the determination interval of the actual fuel injection amount in step S18. Yes, preset.

Further, even if the operation index P is “0” in the determination in step S16 (NO), even in the non-deceleration state and the auxiliary brake inoperative state in the determination in step S17 (NO), or in step S18. Even if the actual fuel injection amount Qm (or the commanded fuel injection amount Qt) is not zero in the determination (Qm ≠ 0, Qt ≠ 0: NO), the process goes to step S20 to turn off the electromagnetic clutch 23 and turn the second oil pump 22 on. Is stopped, and only the first oil pump 21 operates for a predetermined time and returns. This predetermined time is a time related to the determination interval of the operation index in step S14 or S16, the determination interval of the deceleration state or the auxiliary brake operation state in step S17, or the determination interval of the actual fuel injection amount in step S18. Yes, preset. After the return, it will be called again by the advanced flow and will start.

With this control, when the operation state of the internal combustion engine 10 detected by the operation state detection means 41 is a high load state, the deceleration state and the actual fuel injection amount Qm (or the indicated fuel injection amount Qt) are zero, and When the auxiliary brake is in operation and the actual fuel injection amount Qm (or the commanded fuel injection amount Qt) is zero, the amount of engine oil supplied by the variable oil pump 20 can be increased.

Therefore, according to the internal combustion engine 10 and the control method for the internal combustion engine, when the operating state of the internal combustion engine 10 is in a high load state where a large amount of engine oil needs to be supplied, the supply amount of the engine oil is increased and necessary and sufficient. Lubrication and cooling with an appropriate amount of engine oil can be performed efficiently.

Further, in the deceleration state and the auxiliary brake operation state, in order to accurately detect the deceleration state and the braking state of the vehicle, the actual fuel injection amount Qm (or the fuel amount actually injected into the engine from the control device) By further using the determination that the commanded fuel injection amount Qt), which is the commanded amount from the control device 40 to the fuel injection device, is zero, the variable oil pump 20 is in a state where fuel is not reliably injected. Since the supply amount of engine oil can be increased, fuel consumption for this increase can be avoided.

By determining that the actual fuel injection amount Qm (or the indicated fuel injection amount Qt) is zero, a state in which engine fuel is actually still being injected is generated only with a general sensor. In this state, the variable oil pump When 20 is operated, fuel is increased due to this operation, which causes deterioration of fuel consumption of the engine, which is avoided.

Therefore, the energy of the engine drive shaft 12 of the internal combustion engine 10 is recovered while avoiding the deterioration of fuel consumption, the variable oil pump 20 is driven, the supply amount of engine oil is increased, and the engine oil is supplied to the auxiliary brake system 30. The auxiliary braking force can be increased and the necessary braking force can be obtained efficiently.

The internal combustion engine and the control method for the internal combustion engine according to the present invention increase the supply amount of engine oil in a high load state where a large amount of engine oil needs to be supplied, and efficiently perform lubrication and cooling with a necessary and sufficient amount of engine oil. In addition, when the auxiliary brake is activated, the variable oil pump is driven by recovering the energy of the engine drive shaft in a state where fuel is not reliably injected, and the engine oil In the wide range of internal combustion engines such as internal combustion engines mounted on automobiles, construction machines, and internal combustion engines for power generation, it is possible to increase the supply amount, increase the auxiliary braking force, and efficiently obtain the necessary braking force. Available.

DESCRIPTION OF SYMBOLS 10 Internal combustion engine 11 Engine main body 12 Engine drive shaft 13 Gear train 14 Engine speed sensor 15 Fuel injection amount sensor 20 Variable oil pump 21 First oil pump 22 Second oil pump 23 Electromagnetic clutch 30 Auxiliary brake system 31 Electromagnetic valve 32 Exhaust valve Actuating valve 40 Control device 41 Operating state detecting means 50 Vehicle 51 Auxiliary brake actuating switch 52 Accelerator switch 53 Clutch switch 54 Transmission neutral switch Ac Accelerator opening L Engine load Ne Engine speed P Acting index Q Fuel injection amount Qc Calculated Fuel injection amount Qm Actual fuel injection amount Qt Instructed fuel injection amount

Claims

A variable oil pump capable of changing the amount of engine oil supplied with respect to the engine speed of the internal combustion engine, an auxiliary brake system using engine oil supplied from the variable oil pump, and an operating state of the engine are detected. In an internal combustion engine having an operation state detection means and a control device that controls the variable oil pump and the auxiliary brake system, the operation state of the internal combustion engine detected by the operation state detection means is determined by the control device. When the actual fuel injection amount or the commanded fuel injection amount is zero in the deceleration state, and when the actual fuel injection amount or the commanded fuel injection amount is zero in the operation state of the auxiliary brake, An internal combustion engine that performs control to increase the amount of engine oil supplied by a variable oil pump.
The internal combustion engine according to claim 1, wherein the auxiliary brake system is a compression type open brake system in which an exhaust valve of a cylinder of the internal combustion engine is provided with a hydraulically operated valve.
A variable oil pump capable of changing the amount of engine oil supplied with respect to the engine speed of the internal combustion engine, an auxiliary brake system using engine oil supplied from the variable oil pump, and an operating state of the engine are detected. In the control method of an internal combustion engine having the operation state detection means and the control device for controlling the variable oil pump and the auxiliary brake system, the operation state of the internal combustion engine detected by the operation state detection means is a high load. When the actual fuel injection amount or the commanded fuel injection amount is zero in the deceleration state, and when the actual fuel injection amount or the commanded fuel injection amount is zero in the operating state of the auxiliary brake, the variable oil A control method for an internal combustion engine, characterized in that the amount of engine oil supplied by a pump is increased.