WO2019176277A1

WO2019176277A1 - Control device for variable-displacement oil pump and control method therefor

Info

Publication number: WO2019176277A1
Application number: PCT/JP2019/001366
Authority: WO
Inventors: 浩二佐賀; 孝太郎渡辺
Original assignee: 日立オートモティブシステムズ株式会社
Priority date: 2018-03-16
Filing date: 2019-01-18
Publication date: 2019-09-19
Also published as: JP2019157812A

Abstract

According to the present invention, in a state in which the speed of an internal combustion engine (1) is reduced, a target discharge pressure of operating oil supplied from a variable-displacement oil pump (54) is maintained at the current target discharge pressure, and the operating oil is supplied to a hydraulic VTC mechanism (26). Furthermore, after, preferably, an intake valve or an exhaust valve has reached a target phase angle or near the target phase angle, the discharge pressure of the operating oil is reduced, and the operating oil is supplied to the hydraulic VTC mechanism (26). Even in the state in which the speed of the internal combustion engine is reduced, because the discharge pressure of the operating oil from the variable-displacement oil pump (54) is not reduced, it is possible to obtain a quick action of the hydraulic VTC mechanism (26) and to make the valve close to the target phase angle in an early stage by improving the responsiveness of the hydraulic VTC mechanism (26).

Description

Control device and control method for variable displacement oil pump

The present invention relates to a control device and control method for a variable displacement oil pump used in an internal combustion engine, and more particularly to a control device and control method for a variable displacement oil pump that supplies hydraulic oil to a variable valve mechanism.

Conventionally, in a variable displacement oil pump as disclosed in Patent Document 1, the hydraulic oil pressure is generally set lower as the rotational speed of the internal combustion engine is lower, and the hydraulic oil pressure is set higher as the rotational speed is higher. It is supposed to be configured. Further, the hydraulic VTC mechanism is configured so that the rotation of the internal combustion engine operates in a wide range from a low speed range to a high speed range.

By the way, if the amount of depression of the accelerator pedal is reduced in order to decelerate the automobile, the throttle valve is closed correspondingly, and the rotational speed of the internal combustion engine also decreases. When the rotational speed of the internal combustion engine decreases, the target phase angle of the intake valve is also changed to the retarded angle side. Therefore, the hydraulic VTC mechanism changes the phase angle of the intake valve to the retarded angle side. Therefore, it is necessary to control the hydraulic oil.

JP 2012-62789 A

However, in the prior art, the discharge pressure of the hydraulic oil discharged from the variable capacity oil pump is shifted from the high pressure control state to the low pressure control state when the rotational speed is decreased. For this reason, since the discharge pressure of the hydraulic oil supplied to the hydraulic VTC mechanism is rapidly reduced, the operation of the discharge pressure necessary for the early transition of the phase angle of the intake valve from the advanced state to the retarded state is performed. Oil cannot be supplied, and the responsiveness of the hydraulic VTC mechanism (the speed of transition from the current advance position to the target retard position) is deteriorated, resulting in a problem that a good operating state cannot be obtained. . In the above description, the hydraulic VTC mechanism controls the intake valve, but the one that controls the exhaust valve also has the same problem.

An object of the present invention is to provide a control device and a control method for a variable displacement oil pump that can increase the response of a hydraulic VTC mechanism and bring it closer to a target phase angle at an early stage in a state where the rotational speed of the internal combustion engine is reduced. It is in.

The feature of the present invention is that the target discharge pressure of the hydraulic oil supplied from the variable displacement oil pump is maintained at the current target discharge pressure and supplied to the hydraulic VTC mechanism in a state where the rotational speed of the internal combustion engine decreases. Desirably, after the actual phase angle of the intake valve or exhaust valve reaches the target phase angle or near the target phase angle, the target discharge pressure of the hydraulic oil is reduced and supplied to the hydraulic VTC mechanism.

According to the present invention, even when the rotational speed of the internal combustion engine is reduced, the target discharge pressure of the hydraulic oil from the variable displacement oil pump is not lowered, so that the hydraulic VTC mechanism can be operated quickly, and the hydraulic pressure The responsiveness of the VTC mechanism can be improved and the target phase angle can be quickly approached.

1 is a schematic configuration diagram of an internal combustion engine including a hydraulic VTC mechanism according to an embodiment of the present invention. It is a block diagram explaining the change method of the phase angle by the hydraulic VTC mechanism shown in FIG. It is a block diagram explaining the schematic structure of the variable capacity oil pump system in FIG. It is explanatory drawing explaining the 1st pressure control of the hydraulic oil by a variable capacity oil pump. FIG. 5 is a flowchart for explaining a control flow of the first embodiment of the present invention in the first pressure control shown in FIG. 4. It is explanatory drawing explaining the 2nd pressure control of the hydraulic fluid by a variable capacity oil pump. It is a flowchart figure explaining the first half of the control flow of the 2nd Embodiment of this invention in 2nd pressure control shown in FIG. FIG. 7B is a flowchart illustrating the second half of the control flow in FIG. 7A. It is explanatory drawing which shows the change state of the target discharge pressure of the variable capacity oil pump in 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments, and various modifications and application examples are included in the technical concept of the present invention. Is also included in the range.

FIG. 1 is a schematic configuration diagram of an internal combustion engine including a hydraulic VTC mechanism according to an embodiment of the present invention.

The intake pipe 11 for introducing air into each cylinder of the internal combustion engine 1 is provided with an intake air amount sensor 12 for detecting the intake air flow rate QA of the internal combustion engine 1. As the intake air amount sensor 12, for example, a hot-wire flow meter that detects the mass flow rate of intake air can be used.

The intake valve 13 opens and closes the intake port of the combustion chamber 14 of each cylinder, and is provided with a fuel injection valve 15 for each cylinder in the intake pipe 11 upstream of the intake valve 13. The fuel injected from the fuel injection valve 15 is sucked together with air into the combustion chamber 14 via the intake valve 13 and ignited and burned by spark ignition by the spark plug 16, and the pressure by this combustion causes the piston 17 to be applied to the crankshaft 18. The crankshaft 18 is rotationally driven by being pushed down. The crank angle sensor 27 detects the rotation angle of the crankshaft 18 and outputs a reference position signal REF and a unit angle signal POS of the crankshaft 18.

Each ignition plug 16 is directly attached with an ignition module 19 for supplying ignition energy to the ignition plug 16. The ignition module 19 includes an ignition coil and a power transistor that controls energization to the ignition coil.

The exhaust valve 20 opens and closes the exhaust port of the combustion chamber 14, and the exhaust valve 20 is opened so that exhaust gas is discharged to the exhaust pipe 21. A catalytic converter 22 having a three-way catalyst or the like is installed in the exhaust pipe 21, and exhaust gas is purified by the catalytic converter 22. An air-fuel ratio sensor 23 is installed in the exhaust pipe 21 upstream of the catalytic converter 22 to detect the air-fuel ratio A / F based on the oxygen concentration in the exhaust.

The intake valve 13 and the exhaust valve 20 operate with the rotation of the intake camshaft 24 and the exhaust camshaft 25 that are rotationally driven by the crankshaft 18. The intake valve 13 is opened and closed by a cam provided on the intake camshaft 24, and its phase angle (valve opening operating angle) is variable by the hydraulic VTC mechanism 26, so that the valve timing of the intake valve 13 is advanced, Be retarded. The hydraulic VTC mechanism 26 is configured to change the phase angle by switching the hydraulic passage by the solenoid valve 34.

The cam angle sensor 28 detects a reference position signal (intake camshaft rotation angle signal) CAM from the intake camshaft 24. On the other hand, the exhaust valve 20 is driven to open and close by a cam provided on the exhaust camshaft 25.

The water temperature sensor 29 detects the temperature (water temperature) TW of the cooling water of the internal combustion engine 1. The oil temperature sensor 33 detects the oil temperature TO of the hydraulic oil in the oil pan or in the circulation path of the hydraulic oil (engine oil). Further, the accelerator opening sensor 30 detects the amount of depression of the accelerator pedal 31 (accelerator opening ACC).

The control device (control device: Engine Control Unit) 6 includes a microcomputer, and signals from various sensors provided in the internal combustion engine 1, for example, intake air flow rate QA, accelerator opening ACC, reference position signal REF, unit angle A signal POS, an air-fuel ratio A / F, a water temperature TW, an oil temperature TO, a rotation angle signal CAM, and the like are input.

Further, a signal indicating the state of the ignition switch 32 which is a main switch for operating and stopping the internal combustion engine 1 is input to the control device 6. Based on this information, the control device 6 performs arithmetic processing in accordance with a program stored in advance, calculates the operation amounts or control amounts of various devices such as the fuel injection valve 15, the solenoid valve 34, and the ignition module 19, and so on. A control signal is output to the device.

The internal combustion engine 1 can be of various types such as a V type or a horizontally opposed type in addition to the illustrated serial type. Here, the fuel injection valve 15 injects fuel into the intake pipe 11 as an example, but a direct injection type internal combustion engine that injects fuel directly into the combustion chamber 14 may be used. Further, in addition to the intake side VTC mechanism 26, an exhaust side VTC mechanism that makes the opening / closing timing (valve timing) of the exhaust valve 20 variable may be provided.

FIG. 2 shows extracted main parts related to the change of the valve timing by the hydraulic VTC mechanism 26 in FIG. The hydraulic VTC mechanism 26 is disposed at one end of an intake camshaft 24 (see FIG. 1) provided with an intake cam for opening and closing the intake valve 13. The hydraulic VTC mechanism 26 is configured by combining a sprocket 41 that rotates in synchronization with the crankshaft 18 of the internal combustion engine 1 and a rotor 42 that is rotatably connected integrally with the intake camshaft 24 so as to be relatively rotatable. ing. The sprocket 41 is connected to the crankshaft 18 of the internal combustion engine 1 by a timing belt (not shown), and rotates in synchronization with the crankshaft 18.

The sprocket 41 is provided with a cylindrical housing 43 that accommodates the rotor 42. The housing 43 has a cylindrical shape in which both front and rear ends are formed, and the inner circumferential surface has a trapezoidal cross section, and

partition walls

43a, 43b, and 43c provided along the axial direction of the housing 43 respectively protrude. It is installed. A plurality of

vanes

42 a, 42 b, 42 c extending in the radial direction are formed on the outer periphery of the rotor 42, and

accommodating portions

44 a, 44 b, 44 c for accommodating these

vanes

42 a, 42 b, 42 c are formed on the inner periphery of the housing 43. Has been.

Each of the

vanes

42a, 42b, and 42c has a substantially inverted trapezoidal cross section, and the

accommodating portions

44a, 44b, and 44c are separated in the front-rear direction in the rotational direction, and both sides of the

vanes

42a, 42b, and 42c, and the

partition wall portions

43a and 43b. , 43c are formed with advance side

hydraulic chambers

45a, 45b, 45c and retard side

hydraulic chambers

46a, 46b, 46c.

The first hydraulic passage 47 supplies and discharges hydraulic pressure to the advance side

hydraulic chambers

45a, 45b and 45c, and the second hydraulic passage 48 supplies and discharges hydraulic pressure to the retard side

hydraulic chambers

46a, 46b and 46c. To do. A hydraulic oil supply passage 49 and

drain passages

50 and 51 are connected to both the

hydraulic passages

47 and 48 via a passage-switching solenoid valve 34, respectively.

The hydraulic oil supply passage 49 is provided with a variable capacity oil pump 54 that pumps hydraulic oil in the oil pan 53, and the downstream ends of the

drain passages

50 and 51 communicate with the oil pan 53. In the solenoid valve 34, an internal spool valve body 34b relatively controls switching between the

hydraulic passages

47 and 48, the hydraulic oil supply passage 49, and the

drain passages

50 and 51.

The control device 6 controls the energization amount for the solenoid 34a that drives the solenoid valve 34 based on a duty control signal (operation amount) on which a dither signal is superimposed. In the hydraulic VTC mechanism 26, when an off control signal with a duty ratio of 0% is output to the solenoid 34 a, the hydraulic oil pumped from the variable capacity oil pump 54 passes through the hydraulic passage 48 and the retard side

hydraulic chambers

46 a, 46 b, The hydraulic oil in the advance side

hydraulic chambers

45 a, 45 b and 45 c is discharged from the drain passage 51 into the oil pan 53 through the hydraulic passage 47.

As described above, when an OFF control signal with a duty ratio of 0% is supplied to the solenoid, the internal pressure of the retard side

hydraulic chambers

46a, 46b, 46c increases while the internal pressure of the advance side

hydraulic chambers

45a, 45b, 45c decreases. Thus, the rotor 42 rotates to the maximum retardation side via the

vanes

42a, 42b, and 42c. As a result, the opening period of the intake valve 13 changes with a delay relative to the piston position. That is, when the energization to the solenoid 34a is cut off, the central phase of the valve operating angle of the intake valve 13 changes with a delay, and finally stops at the most retarded position.

When an ON control signal with a duty ratio of 100% is output to the solenoid, the spool valve body 34b is driven in the direction of the arrow, and the hydraulic oil is supplied to the advance side

hydraulic chambers

45a, 45b, 45c through the hydraulic passage 47. As the internal pressure increases, the hydraulic oil in the retarded-side

hydraulic chambers

46a, 46b, 46c passes through the hydraulic passage 48 and the drain passage 50 and is discharged to the oil pan 53, where the retarded-side

hydraulic chambers

46a, 46b, 46c The internal pressure is lowered.

In this way, when the ON control signal with a duty ratio of 100% is supplied to the solenoid 34b, the rotor 42 rotates to the maximum advance side via the

vanes

42a, 42b, and 42c, and thereby the opening period of the intake valve 13 is increased. (Center phase of the valve operating angle) changes relative to the piston position.

Therefore, by changing the duty ratio of the control signal supplied to the solenoid 34b, the phase angle of the intake valve 13 can be controlled to an arbitrary position between the most retarded position and the most advanced position. Therefore, by adjusting the advance amount of the intake valve 13 according to the operating state of the internal combustion engine 1, the opening / closing timing, the valve overlap between the intake valve 13 and the exhaust valve 20, etc. can be changed.

FIG. 3 shows a configuration example of a variable displacement oil pump 54 that variably controls the target discharge pressure of hydraulic oil in FIG. 2 in accordance with the rotational speed as shown in FIG.

A suction port and a discharge port are provided on both sides of the pump housing 61, and a drive shaft 62 through which a rotational force is transmitted from the crankshaft 18 of the internal combustion engine 1 is disposed through substantially at the center. Inside the pump housing 61, a rotor 64, which is coupled to a drive shaft 62 and holds a plurality of vanes 63 on the outer peripheral side so as to be able to advance and retreat in a substantially radial direction, is provided on the outer peripheral side of the rotor 64 so as to be able to swing eccentrically. The cam ring 65 in which the tip of each vane 63 is in sliding contact with the inner peripheral surface is accommodated. A pair of vane rings 72 are slidably disposed on both side surfaces on the inner peripheral side of the rotor 64.

The cam ring 65 swings in a direction in which the amount of eccentricity is reduced around the pivot pin 69 in accordance with the discharge pressure introduced into the working

chambers

67 and 68 that are separated by

seal members

66a and 66b on the outer periphery. The coil spring 70 oscillates in a direction in which the amount of eccentricity is increased by the spring force of the coil spring 70 that presses the lever portion 65a integrally provided on the outer periphery thereof.

In the initial state, the cam ring 65 is urged by the spring force of the coil spring 70 in the direction in which the amount of eccentricity is maximized to increase the discharge pressure. On the other hand, when the hydraulic pressure in the working chamber 67 exceeds a predetermined value, The discharge pressure is decreased by swinging in the direction in which the amount of eccentricity is reduced against the spring force of the coil spring 70.

The working oil 67 is supplied from the oil main gallery 73 to the working chamber 67 of the variable capacity oil pump 54, and the working oil is supplied to the working chamber 68 via the proportional solenoid valve 71. The hydraulic VTC mechanism, the oil jet mechanism that cools the piston, the lubrication mechanism for the crank metal that is the bearing portion of the crankshaft, and the like are supplied. The proportional solenoid valve 71 is duty controlled.

When the proportional solenoid valve 71 has a duty of 100%, the working chamber 67 communicates with the drain (oil pan 53) to be in a low pressure state, while when the proportional solenoid valve 71 has a duty of 0%, hydraulic pressure is applied to the working chamber 67. Therefore, it will be in a high pressure state. The discharge pressure is adjusted by the adjusted duty value between 100% duty and 0% duty.

The proportional solenoid valve 71 is supplied with a control signal (duty signal) from the control device 6 which is a control device, whereby the proportional solenoid 71 is driven to the instructed control position. The oil main gallery 73 is provided with a hydraulic pressure sensor 74 that detects the discharge pressure of the variable capacity oil pump 54. The output of the hydraulic sensor 74 is input to the control device 6 and used for feedback control of the discharge pressure of the variable capacity oil pump 54 to the target discharge pressure. Of course, it can be used for other controls.

In such a variable capacity oil pump 54, for example, a discharge pressure is set corresponding to the rotational speed. As shown in FIG. 4, the discharge pressure is set corresponding to the increase in the rotation speed, and the discharge pressure is changed from the minimum discharge pressure to the maximum discharge pressure in the range of the predetermined minimum rotation speed to the predetermined maximum rotation speed. The range is adjusted. The hydraulic oil discharge pressure can be adjusted by the duty ratio of the control signal applied to the proportional solenoid valve 71 (see FIG. 3).

Therefore, if the duty ratio of the control signal is associated with the rotation speed, the target discharge pressure of the variable displacement oil pump 54 is basically variably adjusted according to the rotation speed, and further detected by the hydraulic sensor 74. The discharged pressure is feedback controlled to the set target discharge pressure.

In addition, since it is also possible to perform so-called feedforward control in which the actual discharge pressure is controlled only by the target discharge pressure without performing feedback control, both controls can be applied in this embodiment.

Again, as described above, when the amount of depression of the accelerator pedal is reduced by the driver and the vehicle is decelerated and the number of revolutions of the internal combustion engine is reduced, the discharge pressure of the hydraulic oil discharged from the variable capacity oil pump Is shifted from the high pressure control state to the low pressure control state. For this reason, since the discharge pressure of the hydraulic oil supplied to the hydraulic VTC mechanism is rapidly reduced, the operation of the discharge pressure necessary for the early transition of the phase angle of the intake valve from the advanced state to the retarded state is performed. There is a phenomenon in which oil cannot be supplied, and the responsiveness of the hydraulic VTC mechanism is deteriorated so that a favorable operating state cannot be obtained.

Therefore, in the first embodiment of the present invention, in a state where the rotational speed of the internal combustion engine is reduced, the target discharge pressure of the hydraulic oil supplied from the variable capacity oil pump is maintained at the current target discharge pressure, and the hydraulic VTC mechanism. In addition, after the actual phase angle of the intake valve or exhaust valve reaches the target phase angle or near the target phase angle, the hydraulic oil discharge pressure is reduced and supplied to the hydraulic VTC mechanism. It is what we propose.

Hereinafter, the control flowchart according to the first embodiment will be described with reference to FIG. 5. This control flow is a control flow of the variable displacement oil pump, and the calculation of the target phase angle of the hydraulic VTC mechanism and the hydraulic pressure based on the calculation. The drive control of the VTC mechanism is executed by another VTC control flow. However, the VTC phase angle information such as the target phase angle and the actual phase angle is obtained in the VTC control flow and stored in a well-known work area (RAM), and is read from the work area in step S10 of FIG. 5 described below. Has been issued.

Further, this control flow is started at the start timing every 10 ms cycle, and the start timing is generated by a compare match interrupt of a timer function built in the microcomputer. Then, the following control steps are executed upon arrival of the activation timing.

Here, the following control steps are executed based on a program of the microcomputer, but these control steps can be replaced with a control function executed by the control means (microcomputer).

<< Step S10 >> In step S10, the rotation speed is detected by the crank angle sensor 27, the oil temperature of the hydraulic oil is detected by the oil temperature sensor 33, and the discharge pressure of the hydraulic oil is detected by the hydraulic sensor 74. The set parameters are temporarily stored and stored in the work area of the microcomputer. It should be noted that any other necessary parameters may be detected as appropriate. When a necessary parameter is detected, the process proceeds to step S11.

Although not described here, in the VTC control flow of the hydraulic VTC mechanism, the target phase angle is obtained according to the rotational speed and load, and the actual actual phase angle is detected and stored in the work area of the RAM. ing. Therefore, in this control step, the VTC phase angle such as the target phase angle and the actual phase angle is read from the work area. The hydraulic VTC mechanism performs the operation shown in FIG. 2 based on the VTC control flow.

<< Step S11 >> In Step S11, the current rotational speed (Np) detected in Step 10 is compared with the previous rotational speed (Np-1), and the current rotational speed (Np) is compared with the previous rotational speed (Np). It is determined whether the rotational speed (Np-1) has not changed or is greater than the previous rotational speed (Np-1). This determination is to determine whether the current internal combustion engine speed is constant or increasing (acceleration state), or in other words, whether the internal combustion engine speed is decreasing (deceleration state). It is.

If the rotational speed of the internal combustion engine is constant or increasing, the discharge pressure of the variable displacement oil pump is at least the same as or higher than the current target discharge pressure, so that the response of the hydraulic VTC mechanism deteriorates. If not, the process proceeds to step S12. Here, the current target discharge pressure is the target discharge pressure obtained from the rotation speed detected last time.

On the other hand, if the rotation speed of the internal combustion engine is decreasing, the discharge pressure of the variable displacement oil pump is at least lower than the current target discharge pressure, which may cause a deterioration in the responsiveness of the hydraulic VTC mechanism. As a thing, it transfers to step S13.

<< Step S12 >> Since the rotational speed is constant or increasing in Step S11, it is determined that it is at least equal to or higher than the current target discharge pressure. Therefore, in step S12, as shown in FIG. 4, the duty of the control signal corresponding to the current rotational speed (Np) is calculated and controlled to the target discharge pressure of the variable capacity oil pump corresponding to this duty. To do.

In this case, the actual discharge pressure detected by the hydraulic sensor 74 is compared with the target discharge pressure, and the duty of the control signal is finely adjusted so as to converge to the target discharge pressure. When the target discharge pressure is controlled in step S12, the process returns to the return and waits for the next start timing. In this state, the target discharge pressure of the variable displacement oil pump is at least the same as or higher than the current target discharge pressure, so that the responsiveness of the hydraulic VTC mechanism does not deteriorate.

<< Step S13 >> Since the rotational speed is decreasing in Step S11, the discharge pressure of the variable capacity oil pump is at least lower than the current target discharge pressure. However, if the current rotational speed (Np) is not so much lower than the previous rotational speed (Np-1), it can be considered that there is little risk of a deterioration in the response of the hydraulic VTC mechanism. It ’s good. Therefore, in step S13, the amount of change (ΔN: Np−Np−1) between the current rotational speed (Np) and the previous rotational speed (Np−1) is obtained, and this amount of change (ΔN) is a predetermined amount. It is determined whether or not it is within the range of the change amount threshold (ΔNshd).

If the change amount (ΔN) is within a predetermined change amount threshold value (ΔNshd9) in step S13, the process proceeds to step S12 to execute the control of step S12 described above. If the change exceeds the range of the change amount threshold value (ΔNshd), the target discharge pressure of the variable capacity oil pump is greatly reduced, and the process proceeds to step S14.

Note that this step S13 can be omitted if it is not necessary. In this case, if it is determined in step S11 that the rotational speed is decreasing, the process proceeds to step S14 described below.

<< Step S14 >> In step S14, the target discharge pressure of the variable displacement oil pump corresponding to the previous rotation speed, that is, the current target discharge pressure is maintained. Originally, the target discharge pressure is changed to a low target pressure corresponding to the current rotational speed, but a high target discharge pressure corresponding to the previous rotational speed is maintained by this step. Therefore, in a state where the rotational speed is decreased to a predetermined change amount or more, the target discharge pressure of the hydraulic oil supplied from the variable capacity oil pump is maintained at a high state and supplied to the hydraulic VTC mechanism.

For this reason, even when the rotational speed of the internal combustion engine is decreasing, the target discharge pressure of the hydraulic oil from the variable displacement oil pump is not lowered, so that the hydraulic VTC mechanism can be operated quickly, and the hydraulic pressure VTC It becomes possible to increase the responsiveness of the mechanism and to approach the target phase angle at an early stage. If the target discharge pressure of the variable capacity oil pump corresponding to the previous rotation speed, that is, the current target discharge pressure is maintained, the process proceeds to step S15.

<< Step S15 >> In step S15, the actual phase angle (θa) of the actual intake valve detected by the hydraulic VTC mechanism detected in step S10 is a predetermined angle (Δθ) from the target phase angle (θt) or the target phase angle (θt). ), It is determined whether or not the phase angle near the target phase angle (hereinafter referred to as a set phase angle) is controlled. In the case of this embodiment, the set phase angle (θs) smaller than the target phase angle (θt) by a predetermined phase angle (Δθ) and the actual phase angle (θa) are compared.

The reason for this is that when hydraulic oil having a high target discharge pressure is applied to the hydraulic VTC mechanism until the actual phase angle (θa) reaches the target phase angle (θt), the actual phase angle (θa) becomes the target phase angle (θt). It is because there is a risk of exceeding. For this reason, in this embodiment, the actual phase angle (θa) is obtained by comparing the set phase angle (θs) smaller than the target phase angle (θt) by a predetermined phase angle (Δθ) with the actual phase angle (θa). The target phase angle (θt) is converged with high accuracy. The reason will be described in step S16.

If it is determined in step S15 that the actual phase angle (θa) has not reached the target phase angle, that is, the set phase angle (θs), the determination in step S15 is continued again, and the actual phase angle (θa) If it has been determined that has reached the vicinity of the target phase angle, that is, the set phase angle (θs), the process proceeds to step S16.

<< Step S16 >> In step S16, since the actual phase angle (θs) of the intake valve has reached the set phase angle (θs) by the hydraulic VTC mechanism, the phenomenon that the response of the hydraulic VTC mechanism deteriorates does not occur. First, the target discharge pressure corresponding to the current rotation speed is controlled. As a result, the target discharge pressure becomes lower than the target discharge pressure set in step S14, and is set to a normal target discharge pressure corresponding to the current rotational speed.

Here, in steps S15 and S16, the target discharge pressure is lowered when the set phase angle (θs) smaller than the target phase angle (θt) by a predetermined phase angle (Δθ) is reached, so the vane of the hydraulic VTC mechanism By making the driving force based on the target discharge pressure acting on the pressure smaller than the driving force based on the target discharge pressure set in step S14, the actual phase angle (θa) does not exceed the target phase angle (θt). It becomes possible to calm down.

Of course, if the actual phase angle (θa) can be settled so as not to exceed the target phase angle (θt), the target phase angle (θt) is replaced with the set phase angle (θs) in steps S15 and S16. It is also possible to compare the actual phase angle (θa).

According to the present embodiment, even when the rotational speed of the internal combustion engine is decreasing, the hydraulic oil discharge pressure from the variable displacement oil pump is not reduced, so that the hydraulic VTC mechanism can be operated quickly. In addition, the responsiveness of the hydraulic VTC mechanism can be improved and the target phase angle can be brought closer to the early stage.

Next, a second embodiment of the present invention will be described with reference to FIGS. 6, 7A, and 7B. The basic idea is the same as in the first embodiment, but the setting characteristics of the rotational speed and the target discharge pressure are different. In the first embodiment, as shown in FIG. 4, the target discharge pressure is set almost in proportion to the increase in the rotational speed. However, in the second embodiment, as shown in FIG. The difference is that the target discharge pressure is set stepwise.

As shown in FIG. 6, there are three types of rotation speed range and target discharge pressure. Corresponding to the increase in the rotation speed, the rotation speed (N1) or more and less than the rotation speed (N2) is set as the first pressure control region, and from the rotation speed (N2) or more to the rotation speed (N3), The second pressure control region is set, and the rotation speed (N3) or more is set as the third pressure control region. Here, the rotational speed has a relationship of N1 <N2 <N3.

The first pressure control region is set to the first target discharge pressure (P1), the second pressure control region is set to the second target discharge pressure (P2), and the third pressure control region is set to the third target discharge pressure (P2). P3). In this case, for example, the control duty is set to 80% for the first target discharge pressure (P1), 40% for the second target discharge pressure (P2), and 0% for the third target discharge pressure (P3). Is set. Here, the target discharge pressure has a relationship of P1 <P2 <P3.

Thus, the reason why the target discharge pressure is set stepwise with respect to the increase in the number of revolutions is to reduce the pump drive loss as much as possible and improve the fuel efficiency of the internal combustion engine. For example, if the first pressure control region and the second pressure control region are controlled as shown in FIG. 4, extra work must be performed by the difference between the characteristics of FIG. 4 and FIG. 6, but the control is performed as in this embodiment. This is because the difference described above can be reduced, and as a result, it is not necessary to use the output of the internal combustion engine in vain.

Furthermore, each target discharge pressure is set corresponding to a hydraulic auxiliary mechanism provided in the internal combustion engine, and the first target discharge pressure (P1) corresponds to the hydraulic VTC mechanism, and the second target discharge pressure ( P2) corresponds to the oil jet mechanism, and the third target discharge pressure (P3) corresponds to the crank metal lubrication mechanism.

For this reason, the hydraulic VTC mechanism is driven by hydraulic oil having a target discharge pressure in the first pressure control region, the second pressure control region, and the third pressure control region, and the oil jet mechanism is driven by the second pressure control region and the third pressure control region. The crank metal lubrication mechanism is driven by hydraulic oil having a target discharge pressure in the third pressure control region. Since the oil jet mechanism and the crank metal lubrication mechanism are well-known structures, description thereof is omitted.

Next, the control flow of the present embodiment will be described with reference to FIGS. 7A and 7B. Basically, as in the first embodiment, in the state where the rotational speed of the internal combustion engine decreases, the variable displacement oil pump The target discharge pressure of the hydraulic fluid supplied from the engine is maintained at the current target discharge pressure and supplied to the hydraulic VTC mechanism, and preferably the intake valve or the exhaust valve reaches the target phase angle or near the target phase angle. The hydraulic oil target discharge pressure is reduced and supplied to the hydraulic VTC mechanism.

Note that the responsiveness of the hydraulic VTC mechanism becomes a problem basically when shifting from the second pressure control region to the first pressure control region in the deceleration state in which the rotational speed of the internal combustion engine is decreasing. Hereinafter, control in these two areas will be described. However, it goes without saying that the third pressure control region can also be controlled in the same manner.

<< Step S20 >> Since step S20 is the same control step as step S10 shown in FIG.

<< Step S21 >> In step S21, which pressure control region belongs is determined from the current rotational speed (Np) detected in step 20. For example, if the detected rotational speed (Np) is in the range of N1 or more and less than N2, it is the first pressure control region, and if it is in the range of N2 or more and less than N3, it is the second pressure control region, and N3 or more. Is the third pressure control region. When the current rotational speed (Np) region is obtained, the process proceeds to step S21.

<< Step S22 >> In step S22, the pressure control region of the current rotational speed (Np) is compared with the pressure control region of the previous rotational speed (Np-1), and the current pressure control region is ) Is determined from the pressure control region. This determination is made, for example, by determining whether or not the vehicle remains in the first pressure control region or the second pressure control region in FIG.

If the current rotational speed is in the same pressure control region (first pressure control region or second pressure control region), the target discharge pressure of the variable displacement oil pump is at least the current target discharge pressure (P1 or P2). Therefore, assuming that the response of the hydraulic VTC mechanism does not deteriorate, the process proceeds to step S23. However, the first target discharge pressure (P1) in the first pressure control region is the lowest discharge pressure, but since the rotation speed is low, the transition speed to the target phase angle by the hydraulic VTC mechanism is not so problematic. Don't be.

On the other hand, if the current pressure control region is different from the previous pressure control region, the target discharge pressure of the variable displacement oil pump is at least different from the current target discharge pressure. The process proceeds to step S24 as a possibility of causing deterioration of.

<< Step S23 >> Since it is determined in Step S22 that the pressure control region is the same, in Step S23, the duty of the control signal corresponding to the current pressure control region is calculated as shown in FIG. To the target discharge pressure of the variable capacity oil pump corresponding to

In this case, as in the first embodiment, the actual discharge pressure detected by the hydraulic sensor 74 is compared with the target discharge pressure, and the duty of the control signal is finely adjusted so as to converge to the target discharge pressure. When the target discharge pressure is controlled in step S23, the process returns to the return and waits for the next start timing. In this state, since the target discharge pressure of the variable displacement oil pump is at least the same as the current discharge pressure, the response of the hydraulic VTC mechanism does not deteriorate.

<< Step S24 >> It is determined in step S22 that the current pressure control region is different from the current (previous) pressure control region, and the target discharge pressure of the variable displacement oil pump is at least different from the current target discharge pressure. It becomes. The responsiveness of the hydraulic VTC mechanism becomes a problem when the target discharge pressure becomes low.

Therefore, in step S24, it is determined whether or not the current pressure control region is a pressure control region where the pressure is higher than the current (previous) pressure control region. For example, it is determined whether the transition from the first pressure control region to the second pressure control region or the transition from the second pressure control region to the first pressure control region.

If it is determined in step S24 that the current pressure control region is a pressure control region (second pressure control region) having a higher pressure than the current (previous) pressure control region (first pressure control region), the process proceeds to step S25. Conversely, if it is determined that the current pressure control region is a pressure control region (first pressure control region) whose pressure is lower than the current (previous) pressure control region (second pressure control region), the process proceeds to step S26.

<< Step S25 >> Since it is determined in Step S24 that the pressure control region (second pressure control region) is higher than the current one, in Step S25, as shown in FIG. The duty of the control signal corresponding to the second pressure control region) is calculated and controlled to the target discharge pressure of the variable capacity oil pump corresponding to this duty. For example, the target discharge pressure is set higher by changing the duty from 80% in the first pressure control region to 40% in the second pressure control region.

In this case, as in the first embodiment, the actual discharge pressure detected by the hydraulic sensor 74 is compared with the target discharge pressure, and the duty of the control signal is finely adjusted so as to converge to the target discharge pressure. When the target discharge pressure is controlled in step S25, the process returns to the return and waits for the next start timing. In this state, since the target discharge pressure of the variable displacement oil pump is higher than the current target discharge pressure, the response of the hydraulic VTC mechanism is not deteriorated.

<< Step S26 >> Since it is determined in Step S24 that the pressure control region (first pressure control region) is lower than the current one, in Step S26, the variable corresponding to the previous pressure control region (second pressure control region) is determined. The target discharge pressure of the capacity oil pump, that is, the current target discharge pressure is maintained. Originally, the target discharge pressure is changed to a low target pressure corresponding to the current low pressure control region (first pressure control region), but this step corresponds to the previous pressure control region (second pressure control region). The high target discharge pressure is maintained. Therefore, in a state where the pressure control region is lower than the current level, the target discharge pressure of the hydraulic oil supplied from the variable displacement oil pump is maintained at a high state and supplied to the hydraulic VTC mechanism.

For this reason, even when the rotational speed of the internal combustion engine is decreasing, the discharge pressure of the hydraulic oil from the variable displacement oil pump is not lowered, so that the hydraulic VTC mechanism can be operated quickly, and the hydraulic VTC mechanism It becomes possible to improve the response of the first phase to approach the target phase angle at an early stage. When the target discharge pressure of the variable capacity oil pump corresponding to the current pressure control region (second pressure control region) is maintained, the process proceeds to step S27.

<< Step S27 >> In step S27, the actual phase angle (θa) of the actual intake valve detected by the hydraulic VTC mechanism detected in step S20 is a predetermined angle (Δθ) from the target phase angle (θt) or the target phase angle (θt). ), It is determined whether or not the target phase angle is controlled to the vicinity (hereinafter referred to as a set phase angle). In the case of this embodiment, the set phase angle (θs) smaller than the target phase angle (θt) by a predetermined phase angle (Δθ) and the actual phase angle (θa) are compared.

The reason for this is that when hydraulic oil having a high target discharge pressure is applied to the hydraulic VTC mechanism until the actual phase angle (θa) reaches the target phase angle (θt), the actual phase angle (θa) becomes the target phase angle (θt). It is because there is a risk of exceeding. For this reason, in this embodiment, the actual phase angle (θa) is obtained by comparing the set phase angle (θs) smaller than the target phase angle (θt) by a predetermined phase angle (Δθ) with the actual phase angle (θa). The target phase angle (θt) is converged with high accuracy. The reason will be described in step S28.

If it is determined in step S27 that the actual phase angle (θa) has not reached the target phase angle, that is, has not reached the set phase angle (θs), the determination in step S15 is continued again, and the actual phase angle (θa) When it has been determined that has reached the target phase angle, that is, the set phase angle (θs), the process proceeds to step S28.

<< Step S28 >> In step S28, since the actual phase angle (θs) of the intake valve has reached the set phase angle (θs) by the hydraulic VTC mechanism, the phenomenon that the response of the hydraulic VTC mechanism deteriorates does not occur. First, the target discharge pressure in the pressure control region (first pressure control region) corresponding to the current rotational speed is controlled. Accordingly, the target discharge pressure becomes lower than the target discharge pressure set in step S26, and becomes a normal target discharge pressure corresponding to the rotation speed.

In the present embodiment, the target discharge pressure is lowered when the set phase angle (θs) smaller than the target phase angle (θt) by a predetermined phase angle (Δθ) is reached, so the target discharge acting on the vane of the hydraulic VTC mechanism By making the driving force based on the pressure smaller than the driving force based on the target discharge pressure set in step S26, it is possible to calm the actual phase angle (θa) so as not to exceed the target phase angle (θt). It becomes.

Next, the change state of the target discharge pressure of the variable displacement oil pump when the above control steps are executed will be described.

In FIG. 8, when the rotational speed of the internal combustion engine rises and transitions from the first pressure control region to the second pressure control region, the target discharge pressure as shown by the solid line is obtained by executing steps S22, S24, and S25. Follow the characteristics of In this case, since the target discharge pressure is shifted in the increasing direction, the response of the hydraulic VTC mechanism is not deteriorated.

On the other hand, when the rotational speed of the internal combustion engine decreases and transitions from the second pressure control region to the first pressure control region, by executing steps S22, S26, S27, and S28, the target discharge pressure as shown by the broken line is shown. Follow the characteristics of In this case, since the current target discharge pressure is maintained in step 26, the deterioration of the responsiveness of the hydraulic VTC mechanism can be suppressed. Furthermore, when the actual phase angle of the intake valve reaches the target phase angle in step S27, the flow proceeds to the original target discharge pressure in step S28.

Even in the present embodiment, even when the rotational speed of the internal combustion engine is decreasing, the discharge pressure of the hydraulic oil from the variable displacement oil pump is not lowered, so that the hydraulic VTC mechanism can be operated quickly, The responsiveness of the hydraulic VTC mechanism can be improved and the target phase angle can be brought closer to the early stage.

As described above, the present invention maintains the target discharge pressure of the hydraulic oil supplied from the variable capacity oil pump at the current target discharge pressure and supplies it to the hydraulic VTC mechanism when the rotational speed of the internal combustion engine decreases. Furthermore, it is desirable that the hydraulic oil discharge pressure is reduced and supplied to the hydraulic VTC mechanism after the actual phase angle of the intake valve or exhaust valve reaches the target phase angle or near the target phase angle.

According to this, even when the rotational speed of the internal combustion engine is decreasing, the discharge pressure of the hydraulic oil from the variable displacement oil pump is not lowered, so that the hydraulic VTC mechanism can be operated quickly, and the hydraulic pressure The responsiveness of the VTC mechanism can be improved and the target phase angle can be quickly approached.

In addition, this invention is not limited to above-described embodiment, Various modifications are included. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment. In addition, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

As a control device for a variable displacement oil pump based on the embodiment described above, for example, the following modes can be considered.

A hydraulically driven variable valve mechanism that controls at least the opening timing (hereinafter referred to as phase angle) of an intake valve or an exhaust valve, and a variable displacement oil pump that supplies hydraulic oil to the variable valve mechanism A control apparatus for a variable displacement oil pump used in an internal combustion engine, comprising control means for variably controlling a target discharge pressure of hydraulic oil of the variable displacement oil pump in accordance with a rotational speed of the internal combustion engine, The control means has a function of maintaining the target discharge pressure of the hydraulic oil supplied from the variable displacement oil pump at the current target discharge pressure and supplying it to the variable valve mechanism in a state where the rotation speed of the internal combustion engine decreases. It has.

In a preferred aspect of the control apparatus for the variable displacement oil pump, the control means determines an acceleration state in which the rotational speed is increasing from a change in the rotational speed of the internal combustion engine and a deceleration state in which the rotational speed is decreasing. In the acceleration state, the variable displacement oil pump is controlled so as to be a target discharge pressure corresponding to the detected rotational speed, and in the deceleration state, the current target discharge pressure is maintained. And a function of controlling a variable displacement oil pump.

In another preferred aspect, in any one of the aspects of the control device for the variable displacement oil pump, the control means is configured such that the actual phase angle of the intake valve or the exhaust valve in the deceleration state is a target phase angle, or the target After reaching a set phase angle that is in the vicinity of the phase angle, the hydraulic oil supplied from the variable displacement oil pump is supplied to the variable valve mechanism by reducing the current target discharge pressure.

In another preferable aspect, in any one of the aspects of the control device for the variable displacement oil pump, the set phase angle is set to a phase angle smaller than the target phase angle by a predetermined phase angle.

In another preferred aspect, in any one of the aspects of the control apparatus for the variable displacement oil pump, the control means detects the rotational speed of the internal combustion engine at a predetermined cycle, and the rotational speed detected at the current cycle; A function for determining the acceleration state and the deceleration state from the magnitude of the rotation speed detected in the previous cycle, and the variable capacity so that the target discharge pressure corresponding to the detected current rotation speed is obtained in the acceleration state. A function of controlling the oil pump, and a function of controlling the variable displacement oil pump so as to maintain the target discharge pressure corresponding to the previous rotational speed in the deceleration state.

Further, as another control device of the variable capacity oil pump based on the embodiment described above, for example, the following modes can be considered.

A hydraulically driven variable valve mechanism for controlling at least the opening timing of the intake valve or exhaust valve (hereinafter referred to as a target phase angle), a hydraulic auxiliary mechanism mechanism different from the variable valve mechanism, Used in an internal combustion engine having a variable valve mechanism and a variable displacement oil pump that supplies hydraulic oil to the hydraulic auxiliary mechanism, and has a target discharge pressure of the hydraulic oil of the variable valve mechanism and the hydraulic auxiliary mechanism. A control apparatus for a variable displacement oil pump, comprising control means for variably controlling in accordance with the rotational speed of the internal combustion engine, wherein the control means is at least a predetermined first rotation according to the rotational speed of the internal combustion engine. A first pressure control area corresponding to a number range and a second pressure control area corresponding to a predetermined second speed range higher than the first speed range, and a predetermined value in the first pressure control area First eye A function of setting a discharge pressure and setting a predetermined second target discharge pressure higher than the first target discharge pressure in the second pressure control region; and the second pressure control by reducing the rotational speed of the internal combustion engine. In the state of transition from the region to the first pressure control region, the target discharge pressure of the hydraulic oil supplied from the variable displacement oil pump is maintained at the second target discharge pressure in the second pressure control region, and the variable operation is performed. A function for supplying to the valve mechanism is provided.

In a preferred aspect of the control apparatus for the variable displacement oil pump, when the control means determines that the first pressure control region has transitioned to the second pressure control region, the second pressure control region corresponds to the second pressure control region. When it is determined that the variable pressure oil pump is controlled so as to reach the target discharge pressure, and when the transition from the second pressure control region to the first pressure control region is made, the second pressure control region corresponds to the second pressure control region. And a function of controlling the variable displacement oil pump so as to achieve a target discharge pressure.

In another preferred aspect, in any one of the aspects of the control device for the variable displacement oil pump, the control means is configured such that an actual phase angle of the intake valve or the exhaust valve in a deceleration state of the internal combustion engine is a target phase angle, Alternatively, after reaching a set phase angle that is in the vicinity of the target phase angle, the target discharge pressure of hydraulic oil from the variable displacement oil pump is changed from the second target discharge pressure to the first target discharge pressure, and A function for supplying to the variable valve mechanism is provided.

In another preferred aspect, in any one of the aspects of the control device for the variable displacement oil pump, the control means detects the rotational speed of the internal combustion engine at a predetermined cycle, and the first pressure control is performed based on the detected rotational speed. It has a function of determining whether it is a region or the second pressure control region.

In another preferable aspect, in any one of the aspects of the control device for the variable displacement oil pump, the variable valve mechanism is the first target set in the first pressure control region and the second pressure control region. Driven by hydraulic oil having a discharge pressure and the second target discharge pressure, the hydraulic auxiliary mechanism is an oil jet mechanism, and the oil jet mechanism is set in the second pressure control region. Driven by hydraulic fluid.

Furthermore, as a control method of the variable capacity oil pump based on the embodiment described above, for example, the following modes can be considered.

A hydraulically driven variable valve mechanism that controls at least the opening timing (hereinafter referred to as phase angle) of an intake valve or an exhaust valve, and a variable displacement oil pump that supplies hydraulic oil to the variable valve mechanism A control method for a variable displacement oil pump used in an internal combustion engine, comprising control means for variably controlling a target discharge pressure of hydraulic oil of the variable displacement oil pump in accordance with a rotational speed of the internal combustion engine, The control means detects the rotational speed of the internal combustion engine at a predetermined cycle, the rotational speed detected at the current cycle, and an acceleration state in which the rotational frequency is increased from a change in the rotational frequency detected at the previous cycle, A step of determining a deceleration state where the rotational speed is decreasing, and a step of controlling the variable displacement oil pump so as to achieve a target discharge pressure corresponding to the rotational speed detected in the current cycle in the acceleration state. And-up, in the deceleration state, and a step of controlling the variable capacity oil pump so as to maintain the current target discharge pressure corresponding to a speed detected by the previous cycle.

Further, as another control method of the variable displacement oil pump based on the embodiment described above, for example, the following modes can be considered.

A hydraulically driven variable valve mechanism for controlling at least the opening timing of the intake valve or exhaust valve (hereinafter referred to as a target phase angle), a hydraulic auxiliary mechanism mechanism different from the variable valve mechanism, Used in an internal combustion engine having a variable valve mechanism and a variable displacement oil pump that supplies hydraulic oil to the hydraulic auxiliary mechanism, and has a target discharge pressure of the hydraulic oil of the variable valve mechanism and the hydraulic auxiliary mechanism. A control method for a variable displacement oil pump comprising control means for variably controlling in accordance with the rotational speed of the internal combustion engine, wherein the control means corresponds to at least a predetermined first rotational speed range of the internal combustion engine. From the first target discharge pressure preset in the first pressure control region and the first target discharge pressure preset in the second pressure control region corresponding to the second rotation speed range higher than the first rotation speed range. High second target discharge pressure And determining the transition from the first pressure control region to the second pressure control region, the variable displacement oil pump is controlled to be the second target discharge pressure corresponding to the second pressure control region. And controlling the variable displacement oil pump so as to achieve the second target discharge pressure corresponding to the second pressure control region when it is determined that the transition from the second pressure control region to the first pressure control region is made. To perform the steps.

Claims

A hydraulically driven variable valve mechanism that controls at least the opening timing (hereinafter referred to as phase angle) of an intake valve or an exhaust valve, and a variable displacement oil pump that supplies hydraulic oil to the variable valve mechanism A variable displacement oil pump control device comprising control means for variably controlling a target discharge pressure of hydraulic oil of the variable displacement oil pump corresponding to the rotational speed of the internal combustion engine,
The control means includes
In a state where the rotational speed of the internal combustion engine is reduced, a function is provided in which the target discharge pressure of hydraulic oil supplied from the variable displacement oil pump is maintained at the current target discharge pressure and supplied to the variable valve mechanism. A control apparatus for a variable displacement oil pump.
A control device for a variable displacement oil pump according to claim 1,
The control means includes
A function of determining an acceleration state in which the rotational speed is increasing from a change in the rotational speed of the internal combustion engine and a deceleration state in which the rotational speed is decreasing;
In the acceleration state, the variable displacement oil pump is controlled to achieve a target discharge pressure corresponding to the detected rotational speed, and in the deceleration state, the variable displacement oil pump is maintained so as to maintain the current target discharge pressure. A variable displacement oil pump control device having a function of controlling the pump.
A control device for a variable displacement oil pump according to claim 2,
The control means includes
After the actual phase angle of the intake valve or exhaust valve in the deceleration state reaches a target phase angle or a set phase angle that is close to the target phase angle, the hydraulic oil supplied from the variable capacity oil pump is discharged. A control apparatus for a variable displacement oil pump, comprising a function of reducing a current target discharge pressure and supplying the reduced target valve pressure to the variable valve mechanism.
A control device for a variable displacement oil pump according to claim 3,
The control apparatus for a variable displacement oil pump, wherein the set phase angle is set to a phase angle smaller than the target phase angle by a predetermined phase angle.
A control device for a variable displacement oil pump according to claim 2,
The control means includes
A function of detecting the rotational speed of the internal combustion engine at a predetermined period, and determining the acceleration state and the deceleration state from the rotational speed detected at the current period and the magnitude of the rotational speed detected at the previous period;
In the acceleration state, a function of controlling the variable displacement oil pump so as to achieve a target discharge pressure corresponding to the detected current rotational speed;
And a function of controlling the variable displacement oil pump so as to maintain a target discharge pressure corresponding to the previous rotational speed in the deceleration state.
A hydraulically driven variable valve mechanism for controlling at least the opening timing of the intake valve or exhaust valve (hereinafter referred to as a target phase angle), a hydraulic auxiliary mechanism mechanism different from the variable valve mechanism, Used in an internal combustion engine having a variable valve mechanism and a variable displacement oil pump that supplies hydraulic oil to the hydraulic auxiliary mechanism, and has a target discharge pressure of the hydraulic oil of the variable valve mechanism and the hydraulic auxiliary mechanism. A variable displacement oil pump control device comprising a control means for variably controlling the internal combustion engine according to the rotational speed,
The control means includes
According to the rotational speed of the internal combustion engine, at least a first pressure control region corresponding to a predetermined first rotational speed range and a second pressure control corresponding to a predetermined second rotational speed range higher than the first rotational speed range. A predetermined first target discharge pressure is set in the first pressure control region, and a predetermined second target discharge pressure higher than the first target discharge pressure is set in the second pressure control region. The function to set,
In a state in which the rotational speed of the internal combustion engine is decreased and transitioned from the second pressure control region to the first pressure control region, the target discharge pressure of hydraulic oil supplied from the variable capacity oil pump is set to the second pressure. A control device for a variable displacement oil pump, comprising a function of supplying the variable valve mechanism while maintaining a second target discharge pressure in a control region.
A control device for a variable displacement oil pump according to claim 6,
The control means includes
A function of controlling the variable displacement oil pump so as to be the second target discharge pressure corresponding to the second pressure control region when it is determined that the transition from the first pressure control region to the second pressure control region is performed;
A function of controlling the variable displacement oil pump so as to be the second target discharge pressure corresponding to the second pressure control region when it is determined that the transition from the second pressure control region to the first pressure control region is made; A control apparatus for a variable displacement oil pump, comprising:
A control device for a variable displacement oil pump according to claim 6 or claim 7,
The control means includes
When the actual phase angle of the intake valve or the exhaust valve in the deceleration state of the internal combustion engine reaches a target phase angle or a set phase angle that is close to the target phase angle, the hydraulic oil from the variable displacement oil pump A control device for a variable displacement oil pump, wherein the target discharge pressure is changed from the second target discharge pressure to the first target discharge pressure and supplied to the variable valve mechanism.
A control device for a variable displacement oil pump according to claim 8,
The control apparatus for a variable displacement oil pump, wherein the set phase angle is set to a phase angle smaller than the target phase angle by a predetermined phase angle.
A control device for a variable displacement oil pump according to claim 7,
The control means includes
A variable displacement oil characterized by having a function of detecting the rotational speed of the internal combustion engine at a predetermined cycle and determining whether it is the first pressure control region or the second pressure control region from the detected rotational speed Pump control device.
A control device for a variable displacement oil pump according to claim 6,
The variable valve mechanism is driven by hydraulic fluid of the first target discharge pressure and the second target discharge pressure set in the first pressure control region and the second pressure control region,
The hydraulic auxiliary mechanism is an oil jet mechanism, and the oil jet mechanism is driven by hydraulic oil having the second target discharge pressure set in the second pressure control region. Control device.
A hydraulically driven variable valve mechanism that controls at least the opening timing (hereinafter referred to as phase angle) of an intake valve or an exhaust valve, and a variable displacement oil pump that supplies hydraulic oil to the variable valve mechanism A control method for a variable displacement oil pump, comprising: a control means that is used in an internal combustion engine and variably controls a target discharge pressure of hydraulic oil of the variable displacement oil pump in accordance with a rotational speed of the internal combustion engine,
The control means includes
The number of revolutions of the internal combustion engine is detected at a predetermined period, the number of revolutions detected at the current period, the acceleration state where the number of revolutions has increased from the change in the number of revolutions detected at the previous period, and the number of revolutions decreased. A step of determining a decelerating state,
In the acceleration state, controlling the variable displacement oil pump to a target discharge pressure corresponding to the rotation speed detected in the current cycle;
And a step of controlling the variable displacement oil pump so as to maintain a current target discharge pressure corresponding to the rotational speed detected in the previous cycle in the deceleration state. Control method.
A hydraulically driven variable valve mechanism for controlling at least the opening timing of the intake valve or exhaust valve (hereinafter referred to as a target phase angle), a hydraulic auxiliary mechanism mechanism different from the variable valve mechanism, Used in an internal combustion engine having a variable valve mechanism and a variable displacement oil pump that supplies hydraulic oil to the hydraulic auxiliary mechanism, and has a target discharge pressure of the hydraulic oil of the variable valve mechanism and the hydraulic auxiliary mechanism. A control method for a variable displacement oil pump comprising a control means for variably controlling corresponding to the rotational speed of the internal combustion engine,
The control means includes
At least a first target discharge pressure preset in a first pressure control region corresponding to a predetermined first rotational speed range of the internal combustion engine and a second rotational speed range corresponding to a second rotational speed range higher than the first rotational speed range. Determining a second target discharge pressure higher than the first target discharge pressure set in advance in a two-pressure control region;
Controlling the variable displacement oil pump to be the second target discharge pressure corresponding to the second pressure control region when it is determined that the transition from the first pressure control region to the second pressure control region is performed;
When it is determined that the transition from the second pressure control region to the first pressure control region is made, the step of controlling the variable displacement oil pump so as to be the second target discharge pressure corresponding to the second pressure control region; A control method for a variable displacement oil pump, characterized in that it is executed.