JP6141652B2 - Automotive internal combustion engine - Google Patents

Description

The present invention is related to automotive internal combustion engine characterized by the control during startup.

  Although an idling speed is set in an internal combustion engine for automobiles, it may be difficult to obtain a stable idling speed only by keeping the throttle opening constant. For example, fast idle with warm-up operation is an example. In this regard, Patent Document 1 includes an auxiliary intake valve for warm-up operation, and during the warm-up operation, the ignition timing is retarded to retard the rotation speed. In an internal combustion engine configured to suppress an increase, it is disclosed that the total amount of ignition timing retardation is detected to determine the end of the warm-up time.

That is, the Patent Document 1 is assumed, while the base to increase the heating value by increasing the fuel for the warm-up just speed rapidly increases just opened the throttle opening blow Since the rising phenomenon occurs, the ignition timing is retarded to increase the heat generation while preventing the rotation speed from being increased (swelling up). In Patent Document 1, the retarding control at the time of first idling is assumed. Te, have I row on the basis of the timing of the warm-up end to the cumulative amount of retardation.

  On the other hand, Patent Document 2 discloses that the engine speed is made constant by driving the alternator during fast idling with warm-up and adjusting the load of the heater connected to the alternator. That is, in Patent Document 2, the amount of heat generated by the heater and the alternator drive rate (work rate) are in a proportional relationship, and increasing the amount of heat generated by the heater increases the load of the alternator on the engine and suppresses rotation of the crankshaft. Acts like

JP 2009-264201 A JP 60-56135 A

  Now, for example, if the automobile is stopped for more than a week, the oil accumulated in the lubrication part such as the bearing part of the crankshaft and the bearing part of the camshaft gradually drops down and returns to the oil pan. The phenomenon is seen. Similarly, although the torque converter also uses hydraulic oil, there is a phenomenon that the hydraulic oil gradually falls downward from the operating part such as the pump part and the motor part due to the stop of the torque converter and returns to the oil reservoir part. .

  Then, when the internal combustion engine is started next, the oil pump is driven simultaneously with the start-up, and the oil is pumped to each lubricating part, and the working oil of the torque converter is also sucked up to the working part. It takes a little time to reach, and it takes a little time for the hydraulic oil of the torque converter to reach the working part. There is a state that does not exist, and for this reason, there may occur a phenomenon that the crankshaft rotates at a rotational speed considerably higher than the idling rotational speed at the start.

  In other words, the oil is viscous and acts as a resistance against shaft rotation, etc., but if the internal combustion engine is stopped for a certain period of time, the oil falls off from the lubrication part, etc. The resistance of the oil disappeared, and this caused a phenomenon of blowing up at the beginning of the start.

  Since Patent Documents 1 and 2 are control of rotation after the internal combustion engine is started, it is not possible to cope with the phenomenon of blow-up at the beginning of startup caused by oil dropout.

  The object of the present invention is to prevent the phenomenon of blow-up at the beginning of starting due to the oil drop-off.

In order to achieve the above object, the invention according to claim 1 is the case where it is determined that the amount of oil falling from the lubrication part or the operation part exceeds a preset amount between the stop of operation and the next start. , by adjusting the driving factor of the load variable accessory, the set have that configured so that the engine load during start-up increases with the amount falling off of the oil,
The amount of oil dropout is determined based on the amount of oil in the oil pan, the amount of oil in the oil sump for the transmission, or the engine stop time, and from when the ignition key is turned on until the first explosion occurs, The driving rate of the load variable auxiliary machine is set to be adjusted.

  The present application also includes the invention of claim 2. According to the present invention, in claim 1, an alternator is used as the load variable auxiliary machine.

In the present gun invention, the determination of oil coming off amount may be performed in an oil amount of oil pan or transmission oil sump be detected at a level sensor (oil level) (actually measuring), fall out Oil It is also possible to substitute (estimate) during the operation stop period by utilizing the fact that the amount increases with the operation stop time. These may be used in combination. Furthermore, since the oil drop-off speed is inversely proportional to the viscosity of the oil, it is possible to correct the operation stop period with the outside air temperature so that the load on the auxiliary machine is increased even during a short operation stop period when the outside air temperature is high. .

  The alternator is an example of a load-variable auxiliary machine, and the drive rate (power generation amount) can be arbitrarily adjusted. Therefore, the addition of the alternator to the crankshaft can be arbitrarily adjusted. The alternator is often driven simultaneously with the start of the engine, but generally the drive rate is set lower than 100% in order to prevent engine stall.

  The invention of the present application is to increase the addition of a load variable auxiliary machine such as an alternator at the start, and when the oil falls off the lubrication part and the oil load on the shaft or the like is reduced, the load variable auxiliary machine As a result, the load applied to the crankshaft increases in accordance with the amount of oil that has dropped out, so that it is possible to accurately prevent the phenomenon of blow-up at the beginning of the start due to the oil falling off. Moreover, since energy can be recovered by causing the auxiliary machine to work, it can also contribute to improved fuel efficiency and effective use of fuel.

  Since the alternator can freely adjust the driving rate (load on the crankshaft) by adjusting the exciting current for the winding of the rotor, it is suitable as a load variable auxiliary machine of the present invention. Therefore, by adopting the configuration of the second aspect, it is possible to finely and accurately control the rotation speed of the crankshaft at the time of first idling. Moreover, since the generated electric power can be stored in the battery, it is preferable from the viewpoint of improving fuel consumption.

1 is a conceptual diagram of an internal combustion engine according to an embodiment. It is a graph which shows a control aspect.

(1) Description of Structure Next, an embodiment of the present invention will be described with reference to the drawings. First, the structure will be described with reference to FIG. The internal combustion engine of the present embodiment is a spark ignition type four-cycle internal combustion engine for automobiles, and the number of cylinders is arbitrary, but generally there are three or more cylinders.

  The internal combustion engine has an engine body 3 having a cylinder block 1 and a cylinder head 2 as main elements, and a cylinder head cover 4 that covers the valve mechanism is mounted on the upper surface of the cylinder head 2. An oil pan 5 is fixed to the lower surface of the cylinder head 2. The cylinder block 1 is formed with a cylinder bore 7 in which the piston 6 is slidably fitted. The reciprocating motion of the piston 6 is converted into the rotation of the crankshaft 8.

  The cylinder head 2 is formed with an intake port 9 that is opened and closed by an intake valve (not shown) and an exhaust port 10 that is opened and closed by an exhaust valve. Fresh air is supplied to the intake port 9 from an intake manifold 11. The exhaust gas is discharged from the exhaust port 10 to the exhaust manifold 12. A spark plug 13 is exposed in the combustion chamber provided in the cylinder head 2.

  An intake passage 14 starting from an air cleaner (not shown) is connected to the intake manifold 11, and an electronically controlled throttle valve 15 is provided in the intake passage 14. The fuel is injected into the intake manifold 11 and the intake port 9 or directly into the combustion chamber.

  A chain cover 16 constituting a part of the engine body 3 is fixed to one side surface of the cylinder block 1 and the cylinder head 2, and a valve operating mechanism is provided in a space between the chain cover 16 and the cylinder block 1. A driving timing chain (not shown) is arranged. Although not shown, a transmission including a CVT and a torque converter is attached to the other side of the cylinder block 1 (the back side of the paper).

  One end portion of the crankshaft 8 is exposed to the outside of the chain cover 16, and the rotation detection rotor 17 and the accessory drive pulley 18 are fixed to the exposed portion (the rotation detection rotor 17 is the accessory drive pulley 18). It may be fixed to the inner surface of). The rotation detection rotor 17 is formed in a gear shape having a large number of protrusions on its outer periphery, and a rotation detection sensor 19 facing the outer periphery of the rotation detection rotor 17 is provided on the outer surface of the chain cover 16. By detecting the protrusion of the rotation detection rotor 17 with the rotation detection sensor 19, the angular velocity of the crankshaft 8 can be detected with a fine pitch.

  The engine body 3 is provided with an alternator 20 as an example of a load variable auxiliary machine and a constantly driven water pump 21. The alternator 20 and the water pump 21 are arranged separately on both the left and right sides of the cylinder bore 6 when viewed from the axial direction of the crankshaft 8. Is wrapped around. As another example of the load variable auxiliary machine, an air conditioner compressor may be provided and the air conditioner compressor may be driven by the auxiliary machine driving belt 21.

  The internal combustion engine includes a trochoid oil pump 23. The trochoid type OL pump 23 has a configuration in which an inner rotor and an outer rotor are arranged in a compression chamber between two housings. In this embodiment, one housing is integrally provided on the chain cover 16. The inner rotor is directly connected to the crankshaft 8.

  Oil from the oil pan 5 is sucked into the oil pump 23 via the strainer 24. The oil pumped by the oil pump 23 reaches the discharge port 26 of the oil pump 22 through the oil filter 25, and is pumped from the oil discharge port 26 to the lubrication unit, the oil jet unit, and the like through the oil gallery. Oil that has worked such as lubrication flows down to the oil pan 5 from a return passage provided in the cylinder block 1.

The internal combustion engine includes a battery 29, and the electric power generated by the alternator 20 is consumed as it is or stored in the battery 29. The alternator 20 can arbitrarily adjust the drive rate (power generation amount, load on the crankshaft 8) by adjusting the electromotive force with respect to the winding of the rotor. The battery 29 is provided with a potential level sensor 30.

  The internal combustion engine includes an ECU (engine control unit) 31 as a control device. The ECU 31 is electrically connected to the rotation detection sensor 19, the potential level sensor 30, the spark plug 13, and the throttle valve 15 described above. The ECU 31 is connected to an oil level sensor 33 provided in the oil pan 5, an engine temperature sensor 34 for detecting the coolant temperature, and an outside air temperature sensor 35.

  The ECU 31 is composed of a CPU, various memories, etc., and preferably has a built-in clock (calendar). In the case where the ECU 31 does not have a built-in timepiece, the ECU 31 may be electrically connected to the digital timepiece 36 or the car navigation 37 provided on the vehicle as the time measuring means (period measuring means). By these time measuring means, the history of operation and stop of the internal combustion engine can be recognized over a long period of time. In addition, once driving, the past stop history should be cleared.

(2). Control Mode Next, the control mode of the present invention will be described with reference to FIG. In FIG. 2, (A) shows the first embodiment, which is a basic control mode, and a comparative example in the case of no control. For example, when the internal combustion engine is stopped for more than one week, most of the oil in each lubricating part flows down to the oil pan 5 and the resistance of the oil to the rotation of the shaft or the like is significantly reduced.

  Similarly, even in the torque converter that constitutes the transmission, oil falls from the pump portion and the motor portion to the oil reservoir portion, and the resistance of the oil to the rotation of the pump portion and the motor portion is remarkably reduced. For this reason, if no measures are taken, as shown in the comparative example, there may occur a phenomenon in which the crankshaft rotates at a rotational speed considerably higher than the reference idling rotational speed R0 at the beginning of startup.

  Therefore, when a considerable amount of oil has dropped out, the next start is performed with the drive rate of the alternator 20 higher than the standard state, and the additional amount of drive rate is the amount of oil dropout. It is set to increase proportionally. Then, since the engine is started in a state where the load of the alternator 20 is excessively applied by an amount corresponding to the amount of oil drop-off, the blow-up phenomenon can be accurately prevented as in the first embodiment.

  When the amount of oil dropout is small, there is no noticeable phenomenon of blow-up, so the load increase control at the start is executed after the oil dropout amount reaches a preset amount (for example, 20 to 50% of the total amount). . Since there is some time from when the ignition key is turned on until the starter motor rotates and the first explosion occurs, a sufficient time is required to calculate the drive rate of the alternator 20.

  It is possible to determine from the oil level gauge 33 as one of means for determining whether or not the oil has dropped out to the extent that the blow-up phenomenon occurs at the start, and as one of the means for determining the amount of oil that has dropped out (or the drop-off rate). is there. In other words, since oil is consumed gradually, the amount of oil after the engine has been stopped is memorized by the oil level gauge 33 to calculate the expected storage amount in a state where no oil has dropped out. If the oil actually accumulated in the oil pan 5 is larger than the expected storage amount taking into account the past consumption, it is determined that the storage amount is due to the dropout from the lubrication part. And calculate the difference between the actual storage amount, the expected storage amount and the actual storage amount, and the difference between the storage amount and the actual storage amount when the oil is completely removed. The drive rate addition amount of the alternator 20 is calculated based on a preset map, and the engine is started at the drive rate obtained by adding the addition amount to the standard drive rate.

It is also possible to provide an oil sensor in the oil reservoir of the transmission and predict the possibility of a blow-up phenomenon from the amount of oil that has dropped out of the transmission. Alternatively, the determination based on the operation stop period, the determination based on the value of the oil level sensor 33 of the oil pan 5, and the determination based on the value of the oil sensor of the transmission may be used together (for example, The set values of the three variables are determined, and the drive control of the alternator 20 is executed when each variable exceeds the set value.)

  An operation stop period can be used as another method for determining whether or not oil has fallen to such an extent that a blow-up phenomenon occurs at start-up. That is, the oil gradually drops until a certain period after the operation is stopped. For example, when the operation is stopped for about one week, the oil often drops out, so that the alternator 20 is driven based on the operation stop period. The amount of rate added can be determined.

  In this case, as shown by the dotted comparative examples 1, 2, and 3 in FIG. 2A, the resistance of the oil to the engine drive differs depending on the amount of oil dropout, and the oil dropout amount differs depending on the operation stop period. Therefore, the additional amount of the drive rate of the alternator 20 is set so as to increase according to the length of the operation stop period. For example, if the oil drop becomes significant after 3 days (72 hours) of operation stoppage and oil stops completely after 1 week (168 hours), the control start condition is 72 hours, and it reaches 168 hours. It is possible to control such that the drive addition rate is gradually increased according to the operation stop time until the maximum addition rate is maintained when the operation stop time has passed 168 hours.

  As a control in a state where the oil drop continues, it is possible to increase stepwise instead of increasing the addition rate steplessly according to the length of the stop time (period). . For example, it is possible to control 40% of the maximum addition amount in the case of stopping for 60 to 100 hours, 75% of the maximum addition amount in the case of over 100 to 160 hours, and 100% addition amount after 160 hours. . It is also possible to calculate the drive rate of the alternator 20 by combining the operation stop period and the detected value of the oil level sensor 33.

  Since the oil enters the lubrication portion and the like, the resistance of the oil to the shaft and the like increases. Therefore, if the alternator 20 is continuously driven, the rotation speed of the crankshaft 8 decreases to a reference rotation speed R0 or less. Therefore, when the oil reaches the entire engine, the drive rate of the alternator 20 is returned to the standard state.

  The determination that the oil has spread throughout the engine (that is, the timing for returning the alternator 20 to the standard state) may be made in the elapsed time from the start (for example, several seconds), and the rotational speed is up to the reference rotational speed R0. You may judge by having fallen, or you may carry out by the elapsed time from the peak of rotation speed. Since the resistance of the oil to the rotation increases according to the oil spread, the rotational fluctuation can be almost eliminated by gradually decreasing the drive rate of the alternator 20 over a predetermined time.

  As described above, the drive rate of the alternator 20 at the start is adjusted according to the amount of oil drop-off, and in conjunction with this, the drive rate of the alternator 20 is finely adjusted based on the magnitude of the angular velocity of the crankshaft 8. It is also possible to do.

  For example, as shown in FIG. 2A, the angular velocity change rate (slope) per unit time is calculated by dividing the angular velocity change amount and ΔR by the time change amount Δt, and this angular velocity change rate is calculated. It is possible to change the additional amount of the drive rate of the alternator 20 according to the above.

As shown in Examples 2-4 of FIG. 2 (B) ~ (D), the reference angular velocity (reference speed) and allowed to set the upper limit R1 and lower R2 target zone around the R0, real When the angular velocity exceeds the reference angular velocity R0, the drive rate (addition amount) of the alternator 20 is increased, and when the angular velocity falls below the reference rotational speed R0, the drive rate (addition amount) of the alternator 20 is decreased. Thus, when the rotational speed is converged to the reference rotational speed R and the rotational speed is converged to the reference rotational speed R, the drive of the alternator 20 can be returned to the standard state.

  If a predetermined amount of rotation speed decrease is observed during a preset time after the start, it is determined that there is a possibility of misfire, and the drive of the alternator 20 itself is stopped, or the drive rate of the alternator 20 is increased. Returning to the standard state (a reference value is set for the rate of decrease, and if it is larger than the reference value, the drive of the alternator 20 itself is stopped, and if it is smaller than the reference value, it can be controlled to return to the standard state. ).

  On the other hand, if the rotational speed does not decrease but the angular speed does not reach the reference rotational speed R0 even after starting, the drive rate of the alternator 20 may be returned to the standard state. In that case, if the drive of the alternator 20 is returned to the standard state and the angular velocity is located between the upper limit R1 and the lower limit R2, the drive rate of the alternator 20 is maintained in the standard state. On the other hand, if the angular velocity exceeds the reference rotational speed R0 by returning the drive rate of the alternator 20 to the standard state, it is determined that a blow-up phenomenon may occur, and the drive rate of the alternator 20 can be increased again. Good. That is, feedback control may be performed in accordance with the amount of deviation between the actual angular velocity and the reference rotational speed R0.

  If the rotational speed does not increase even after the drive of the alternator 20 is stopped, the ignition timing can be advanced. That is, the present invention can be used in combination with ignition timing control.

  In the above embodiment, the alternator is used as the load variable auxiliary machine. However, when the compressor of the air conditioner is driven by the crankshaft, the compressor of the air conditioner can be used as the load variable auxiliary machine. In this case, if the fan of the air conditioner is stopped, no cool air is sent into the vehicle, so that the passenger does not feel uncomfortable. Further, since the compressor driving time is very short, it can be said that the function of the air conditioner itself is not exhibited. It is also possible to drive both the alternator 20 and the compressor of the air conditioner.

Since the moving speed of the piston is not constant but is different, the angular speed of the crankshaft also changes according to the rotation angle. That is, the angular velocity of the crankshaft periodically changes so as to become the highest at the initial stage of the explosion stroke. For example, in the case of a three-cylinder four-cycle engine, this cycle changes at a cycle of 270 degrees when viewed from the rotation angle of the crankshaft. In the actual control of the present invention, the position at which the angular velocity is viewed becomes a problem. In this regard, it can be said that the angular velocity should be viewed at the instantaneous maximum angular velocity. This is because the torque of the crankshaft is most reflected at the instantaneous maximum angular velocity.

  The ease of oil removal from the lubrication part etc. is proportional to the viscosity, and the viscosity is inversely proportional to the temperature, so the outside air temperature is taken into the control system and the drive rate of the alternator and the control start time are corrected according to the outside air temperature. It is also possible. That is, it is possible to control the outside air temperature to be divided into several zones in an appropriate range (for example, in 5 degree increments), and the control start time is advanced as the temperature increases.

  When the engine is started without driving a load variable auxiliary machine such as an alternator, the drive rate of the load variable auxiliary machine may be set according to the amount of oil dropout.

The present invention can actually be applied to the combustion engine for an automobile. Therefore, it can be used industrially.

DESCRIPTION OF SYMBOLS 1 Cylinder block which comprises an engine main body 2 Cylinder head which comprises an engine main body 3 Engine main body 5 Oil pan 8 Crankshaft 16 Chain cover which comprises an engine main body 17 Rotation detection rotor 18 Auxiliary drive pulley 19 Rotation detection sensor 20 Variable load type Alternator as an example of auxiliary machine 22 Auxiliary machine drive belt 29 Battery 30 Potential level sensor 31 ECU as control means
33 Oil level sensor
35 Outside air temperature sensor 36 Digital clock 37 Car navigation

Claims (2)

Adjust the drive rate of the load-variable auxiliary machine when it is determined that the amount of oil falling from the lubrication part or working part has exceeded a preset amount between the stop of operation and the next start accordingly, the engine load at the time of start-up a structure that is configured to increase in accordance with the amount falling off of the oil,
The amount of oil dropout is determined based on the amount of oil in the oil pan, the amount of oil in the oil sump for the transmission, or the engine stop time, and from when the ignition key is turned on until the first explosion occurs, It is set so that the drive rate of the load variable auxiliary machine is adjusted.
Automotive internal combustion engine. The load variable auxiliary machine is an alternator,
The internal combustion engine according to claim 1.

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