JP2011179627A - Apparatus for controlling power transmission device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately calculate degree of progression of air inclusion in an operating oil, concerning a power transmission device for a vehicle that controls each rotary drive of two rotating members separately. <P>SOLUTION: An apparatus sequentially calculates the degree of air inclusion in the operating oil per unit time, based on each rotation speed (rotating speed of engine N<SB>E</SB>and rotating speed of a second electric motor N<SB>MG2</SB>) of two rotating members whose degrees of contribution of air inclusion with respect to the operating oil are different from each other and according to a map for estimating the amount of inclusion of bubbles, and then sequentially calculates the degree of progression of air inclusion in the operating oil, by counting up the degree of air inclusion. Accordingly, concerning the power transmission device 10 that controls each rotary drive of two rotating members separately, the degree of progression of air inclusion in the operating oil that is involved in a speed change of an automatic transmission device 18, is accurately calculated (estimated). By the calculation technique, a proper processing such as changing hydraulic control for a speed change of the automatic transmission device 18, is allowed to be performed with respect to the air inclusion in the operating oil. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a differential mechanism that is connected to an engine so as to be capable of transmitting power and whose differential state is electrically controlled, and an automatic transmission that performs a shift by supplying and discharging hydraulic oil to and from a hydraulic friction engagement device. And an electric motor connected to an output shaft of a differential mechanism via an automatic transmission so as to be able to transmit power, and more particularly to a technique for coping with air contamination in hydraulic oil. Is.

  The differential mechanism is connected to the engine so as to be able to transmit power, and the differential motor is connected to the differential mechanism so as to be capable of transmitting power, and the differential motor is controlled by controlling the operating state of the differential motor. 2. Description of the Related Art A vehicle power transmission device is well known that includes an electric transmission mechanism in which a differential state of a mechanism is controlled, and a traveling motor that is coupled to an output shaft of the electric transmission mechanism via a transmission so that power can be transmitted. It has been. In addition, as the transmission, for example, there is an automatic transmission in which a shift is executed by controlling the supply and discharge of hydraulic oil to and from the hydraulic friction engagement device by a hydraulic control circuit and a predetermined shift stage is established. Well known.

  On the other hand, for example, air may be mixed into the hydraulic oil in the hydraulic control circuit due to stirring by a rotating member (rotating member, rotating element) constituting the vehicle power transmission device including the automatic transmission. If gear shifting is performed with air mixed in the hydraulic oil, for example, the desired engagement transient hydraulic pressure for controlling the engagement-side hydraulic friction engagement device toward the engagement cannot be obtained, and the shift shock increases. May be incurred. For example, Japanese Patent Application Laid-Open No. H10-228707 discloses a countermeasure against such air contamination based on the rotation speed of the rotating member including the hydraulic friction engagement device and the duration of the hydraulic friction engagement device being left in the released state. By determining the progress of air mixing in the hydraulic oil and supplying the hydraulic pressure within a range where the piston does not stroke when the mixing progress exceeds a predetermined value. It has been proposed to discharge air mixed in hydraulic oil.

JP 2002-276696 A JP 2002-235848 A JP 2004-144233 A JP 2000-97326 A

  By the way, in the case of a vehicle power transmission device configured such that a traveling motor is provided on the output shaft of the electric transmission mechanism via a transmission, a factor causing air to be mixed into the hydraulic oil, that is, foaming (stirring) of the hydraulic oil. The engine rotation drive and the driving motor rotation drive, which are factors that affect the engine, are independently controlled. For example, the agitation state of the hydraulic oil differs depending on the combination of these controls. Since the rotational speed of each of the speed and the motor speed for traveling is different from the contribution to air mixing, the progress of air mixing can be accurately estimated (determined) from the rotational speed of a single rotating member. May not be possible. Further, for example, if the progress of air mixing cannot be accurately estimated, there is a possibility that an appropriate measure cannot be executed for air mixing. Such a problem is not yet known.

  The present invention has been made in the background of the above circumstances, and the object of the present invention is to change the speed of an automatic transmission in a vehicle power transmission device in which the rotational driving of two rotating members can be controlled independently. It is an object of the present invention to provide a control device capable of accurately calculating the degree of air mixing in the hydraulic oil so that appropriate measures can be taken against the air mixing in the hydraulic oil involved in the operation.

  To achieve the above object, the gist of the present invention is that: (a) a differential mechanism connected to an engine so as to be able to transmit power and a differential motor connected so as to be able to transmit power to the differential mechanism; An electric transmission mechanism in which the differential state of the differential mechanism is controlled by controlling the operating state of the differential motor, and the supply and discharge of hydraulic oil to and from the hydraulic friction engagement device are controlled. Control of a vehicle power transmission device comprising: an automatic transmission in which a shift stage is established, and a traveling motor connected to an output shaft of the electric transmission mechanism through the automatic transmission so as to transmit power (B) the rotational speed of the hydraulic oil per unit time can be controlled independently based on the rotational speed of each of the two rotating members whose rotational speed is independently controllable and whose contribution to the air mixing is different. Pre-set to calculate the degree of air contamination (C) sequentially calculating the air mixing degree per unit time based on the rotational speed of each of the two rotating members from the relationship, and (d) counting the air mixing degree. It is to sequentially calculate the degree of air mixing in the hydraulic oil.

  In this way, the degree of air contamination per unit time based on the rotational speed of each of the two rotating members based on the preset relationship for calculating the degree of air contamination in the hydraulic oil per unit time. Are sequentially calculated, and the degree of air mixing in the hydraulic oil is sequentially calculated by counting the air mixing degree, so that the rotational drive of the two rotating members can be independently controlled. Therefore, it is possible to accurately calculate (estimate) the degree of air mixing in the hydraulic oil involved in the shift of the automatic transmission (that is, the air bubble content). As a result, for example, it is possible to execute an appropriate measure against air contamination in the hydraulic oil, such as changing the hydraulic control related to the shift of the automatic transmission. The electric transmission mechanism can be operated as a stepped transmission by changing the gear ratio stepwise, in addition to operating as an electric continuously variable transmission by continuously changing the gear ratio. It is.

  Here, preferably, when the sequentially calculated degree of progress of air mixing exceeds a predetermined value, hydraulic control related to shifting of the automatic transmission is changed. If it does in this way, it will become easy to discharge | emit air from hydraulic oil according to the progress degree of air mixing in the hydraulic oil which participates in the shift of an automatic transmission, for example, and it will become possible to suppress the increase in a shift shock.

  Preferably, the automatic transmission is controlled by controlling the supply and discharge of hydraulic oil to and from the hydraulic friction engagement device in accordance with a preset shift line so that an optimum shift stage is selected. The optimum gear is established, and at least the upshift line of the preset shift lines is selected so that the optimum gear is selected, and the high gear ratio side selects the upshift line. It is to change the hydraulic control related to the shift of the automatic transmission by changing to a preset upshift line so that it can be easily performed. In this way, for example, when the degree of air mixing in the hydraulic oil exceeds a predetermined value, the automatic transmission is easily upshifted, and the rotational speed of the motor for traveling due to the upshift of the automatic transmission is increased. As a result of the decrease, the agitation of the hydraulic oil is reduced and air is easily discharged from the hydraulic oil. In other words, the upshift can be performed early before the shift shock worsens, and the shift shock during the actual upshift is appropriately suppressed.

  Preferably, the automatic transmission is a mechanical transmission mechanism in which a gear position is switched by engagement and release of the hydraulic friction engagement device, and the engagement-side hydraulic friction engagement mechanism due to air mixing. The hydraulic control related to the shift of the automatic transmission is changed by delaying the lowering of the hydraulic pressure of the release-side hydraulic friction engagement device so as to compensate for the increase in hydraulic pressure of the combined device. In this way, for example, when the degree of air mixing in the hydraulic oil exceeds a predetermined value, the decrease in the release side hydraulic pressure in the shift transient process is likely to be delayed, and the rotation of the traveling motor in the shift transient process is facilitated. It becomes easy to suppress the increase (blowing) of the speed. That is, for example, even when the degree of air mixing in the hydraulic oil exceeds a predetermined value, a shift shock during actual shift is appropriately suppressed.

  Preferably, the two rotating members are a rotating member of the differential mechanism that is rotationally driven by the engine and a rotating member of the automatic transmission that is rotationally driven by the electric motor for traveling. In this way, a preset relationship for calculating the degree of air mixing in the hydraulic oil per unit time is appropriately provided, and based on the rotational speed of each of the two rotating members based on the relationship. The air mixing degree is calculated appropriately. Then, the degree of air mixing in the hydraulic oil is appropriately calculated by counting the degree of air mixing.

  Preferably, the rotation speed of each of the two rotating members is the rotation speed of the engine and the rotation speed of the electric motor for traveling. In this way, a preset relationship for appropriately calculating the degree of air mixing in the hydraulic oil per unit time based on the rotational speed of the engine and the rotational speed of the electric motor for traveling is appropriately provided. From this relationship, the air mixing degree is appropriately calculated based on the rotational speed of the engine and the rotational speed of the traveling motor. Then, the degree of air mixing in the hydraulic oil is appropriately calculated by counting the degree of air mixing.

  Preferably, the preset relationship for calculating the degree of air mixing is set such that the degree of air mixing increases as the rotational speed of the engine increases, and the rotational speed of the electric motor for traveling is increased. The higher the is, the higher the air mixing degree is. In this way, a preset relationship for calculating the degree of air contamination in the hydraulic oil per unit time based on the rotational speed of the engine and the rotational speed of the traveling motor is more appropriately provided. .

  Preferably, in the automatic transmission, for example, a plurality of gear stages (shift stages) are alternatively selected by selectively connecting rotating members of a plurality of sets of planetary gear devices by a hydraulic friction engagement device. For example, it is constituted by various planetary gear type multi-stage transmissions having two forward speeds, three forward speeds, and more. As this hydraulic friction engagement device, a hydraulic friction engagement device such as a multi-plate type, single plate type clutch or brake engaged by a hydraulic actuator, or a belt type brake is widely used. An oil pump that supplies hydraulic oil for engaging and operating the hydraulic friction engagement device may be driven to rotate by an engine that is a driving force source for traveling, for example, and discharges hydraulic oil. It may be rotationally driven by a dedicated electric motor provided separately.

  Preferably, the hydraulic control circuit including the hydraulic friction engagement device directly outputs, for example, an output hydraulic pressure of a linear solenoid valve as an electromagnetic valve device to a hydraulic actuator (hydraulic cylinder) of the hydraulic friction engagement device. It is desirable to supply each of them in terms of responsiveness, but by using the output hydraulic pressure of the linear solenoid valve as a pilot hydraulic pressure, the shift control valve (shift control valve) is controlled and hydraulic oil is supplied from the control valve to the hydraulic actuator. It can also be configured to supply. The linear solenoid valve is provided, for example, corresponding to each of a plurality of hydraulic friction engagement devices, but a plurality of hydraulic solenoid valves that are not simultaneously engaged, engaged, or controlled to be released. When a friction engagement device exists, various modes are possible, such as providing a common linear solenoid valve for them. In addition, it is not always necessary to perform the hydraulic control of all the hydraulic friction engagement devices with the linear solenoid valve. Some or all of the hydraulic control may be pressure control means other than the linear solenoid valve, such as duty control of the ON-OFF solenoid valve. You can go there. In this specification, “supplying hydraulic pressure” means “applying hydraulic pressure” or “supplying hydraulic oil controlled to the hydraulic pressure”.

  Preferably, the differential mechanism is connected to the first rotating element (rotating member) connected to the engine, the second rotating element (rotating member) connected to the differential motor, and the output shaft. It is an apparatus which has three rotation elements (rotation member) with the 3rd rotation element (rotation member) made. In this way, the differential mechanism is easily configured.

  Preferably, the differential mechanism is a single pinion type planetary gear device, the first rotating element is a carrier of the planetary gear device, and the second rotating element is a sun gear of the planetary gear device. The third rotating element is a ring gear of the planetary gear device. In this way, the axial direction dimension of the differential mechanism is reduced. Further, the differential mechanism is simply constituted by one single pinion type planetary gear device.

  Preferably, the mounting posture of the vehicle power transmission device with respect to the vehicle may be a horizontal type such as an FF (front engine / front drive) vehicle in which the axis of the driving device is in the width direction of the vehicle. A vertical installation type such as an FR (front engine / rear drive) vehicle in which the vehicle is in the longitudinal direction of the vehicle may be used.

  Preferably, the engine and the differential mechanism may be operatively connected. For example, a pulsation absorbing damper (vibration damping device), a direct coupling clutch, and a damper are provided between the engine and the differential mechanism. A direct coupling clutch or a fluid transmission device may be interposed, but an engine and a differential mechanism may be always connected. As the fluid transmission device, a torque converter with a lock-up clutch, a fluid coupling, or the like is used.

  Preferably, an internal combustion engine such as a gasoline engine or a diesel engine is widely used as the engine. Further, an electric motor or the like may be used in addition to the engine as a driving power source for auxiliary traveling.

It is a figure explaining the hybrid vehicle to which this invention is applied. It is a collinear diagram showing the relative relationship of the rotational speed of each rotation element in the power distribution mechanism with which the power transmission device for vehicles was equipped. It is a collinear diagram showing the mutual relationship of each rotation element about the Ravigneaux type planetary gear mechanism which comprises the automatic transmission with which the power transmission device for vehicles was equipped. It is a hydraulic control circuit for controlling the shift of the automatic transmission by disengaging the first brake and the second brake. It is a figure which shows the valve characteristic of the 1st linear solenoid valve of a normally open type which is valve-opened (communication) between an input port and an output port at the time of non-energization. It is a figure which shows the valve characteristic of the 2nd linear solenoid valve of a normally closed type by which the port between an input port and an output port is closed (shut off) at the time of non-energization. It is a graph explaining the action | operation of a hydraulic control circuit. It is a functional block diagram explaining the principal part of the control function of an electronic controller. In the engine fuel consumption map, a broken line is an optimum fuel consumption rate curve of the engine set in advance experimentally so as to achieve both drivability and fuel efficiency. It is a shift diagram used in the shift control of an automatic transmission. It is a figure which shows an example of the hydraulic oil foam content with respect to a 2nd electric motor rotational speed. It is a figure which shows an example of the hydraulic oil foam content with respect to an engine speed. It is a preset relationship (bubble content estimation map) for calculating the degree of air contamination in the hydraulic oil per unit time based on the engine rotation speed and the second motor rotation speed. It is a shift diagram used when the air mixing progress degree in hydraulic oil exceeds a predetermined value. Explains the control operation of the electronic control unit, that is, the control operation for accurately calculating the degree of air mixing in the hydraulic oil so that appropriate measures can be taken against the air mixing in the hydraulic oil It is a flowchart to do. It is a time chart which shows an example at the time of performing the control action shown to the flowchart of FIG. Explains the control operation of the electronic control unit, that is, the control operation for accurately calculating the degree of air mixing in the hydraulic oil so that appropriate measures can be taken against the air mixing in the hydraulic oil This is another embodiment corresponding to the flowchart of FIG. It is a time chart which shows an example at the time of performing the control action shown to the flowchart of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a hybrid vehicle (hereinafter referred to as a vehicle) 8 to which the present invention is preferably applied. A vehicle 8 shown in FIG. 1 has a power distribution mechanism 16 that distributes power output from an engine 12 as a main power source to a first electric motor MG1 and an output shaft 14 as a transmission member, and automatic transmission to the output shaft 14. A vehicle power transmission device (hereinafter referred to as a power transmission device) 10 having a second electric motor MG2 as a traveling electric motor operatively connected via a machine 18 (to allow power transmission). The power transmission device 10 is suitably used for an FR (front engine / rear drive) vehicle or the like, and torque output from the engine 12, the second electric motor MG2, etc. is transmitted to the output shaft 14, and the output thereof. Torque is transmitted from the shaft 14 to the pair of left and right rear wheels (drive wheels) 22 via the differential gear device 20. In addition, since the power transmission device 10 is configured symmetrically with respect to the center line, FIG. 1 omits half of them.

In the power transmission device 10, the torque transmitted from the second electric motor MG2 to the output shaft 14 becomes a gear ratio γs (= the rotational speed N _{MG2 of MG2} / the rotational speed N _OUT of the output shaft 14) set in the automatic transmission 18. Increase or decrease accordingly. This automatic transmission 18 is configured to be able to establish a plurality of speeds with a gear ratio γs larger than “1”, and during the power running that outputs the output torque T _MG2 from the second electric motor MG2, the MG2 torque T _MG2 thereof. Can be transmitted to the output shaft 14, so that the second electric motor MG <b> 2 can be configured to have a lower capacity or a smaller size. Thus, for example, when the rotational speed of the output shaft 14 increases with a high vehicle speed, the speed ratio γs of the automatic transmission 18 is reduced in order to maintain the operating efficiency of the second electric motor MG2 in a good state. The rotation speed of the second electric motor MG2 (second electric motor rotation speed) N _MG2 is lowered by setting it to the high gear ratio side. When the rotational speed of the output shaft 14 decreases, the second motor rotational speed _NMG2 is appropriately increased by increasing the speed ratio γs of the automatic transmission 18 (to the low gear ratio side).

  The engine 12 is a main power source of the vehicle 8 and is a known internal combustion engine that outputs power by burning predetermined fuel, such as a gasoline engine or a diesel engine. The vehicle 8 is provided with an electronic control unit 150 mainly composed of a microcomputer, and the engine 12 is controlled by an engine control electronic control unit (E-ECU) included in the electronic control unit 150 according to a throttle opening degree or The operation state such as the intake air amount, the fuel supply amount, and the ignition timing is electrically controlled. The engine control electronic control unit (E-ECU) includes an accelerator opening sensor AS for detecting the operation amount of the accelerator pedal 24, a brake sensor BS for detecting the operation of the brake pedal 26, and the like. A detection signal is supplied.

The first electric motor MG1 and the second electric motor MG2 are, for example, synchronous motors having at least one of a function as an electric motor (motor) for generating a drive torque and a function as a generator (generator), and preferably A motor generator that is selectively operated as a motor or a generator. The first electric motor MG1 and the second electric motor MG2 are connected to a power storage device 32 such as a battery or a capacitor via inverters 28 and 30, and an electronic control device (MG-ECU) for motor generator control included in the electronic control device 150. ) Controls the inverters 28 and 30 so that the output torque or regenerative torque of the first electric motor MG1 and the second electric motor MG2 is adjusted or set. The motor generator control electronic control unit (MG-ECU) includes an operation position sensor SS for detecting the operation position of the shift lever 34, and the rotation speed of the output shaft 14 corresponding to the vehicle speed (output shaft rotation speed). A detection signal from an output rotational speed sensor NOS or the like for detecting N _OUT is supplied.

  The power distribution mechanism 16 includes a sun gear S0, a ring gear R0 arranged concentrically with respect to the sun gear S0, and a carrier CA0 that supports the sun gear S0 and the pinion gear P0 meshing with the ring gear R0 so as to rotate and revolve freely. It is comprised from the well-known single pinion type planetary gear apparatus provided as a rotation element (rotation member), and functions as a differential mechanism which produces a differential action. This planetary gear device is provided concentrically with the engine 12 and the automatic transmission 18. Further, in the power transmission device 10, the crankshaft 36 of the engine 12 is connected to the carrier CA0 of the power distribution mechanism 16 via a damper 38. On the other hand, the first motor MG1 is connected to the sun gear S0, and the output shaft 14 is connected to the ring gear R0. In the power distribution mechanism 16, the carrier CA0 functions as an input element, the sun gear S0 functions as a reaction force element, and the ring gear R0 functions as an output element.

The relative relationship of the rotational speed of each rotating element (rotating member) in the power distribution mechanism 16 is shown by the alignment chart of FIG. In this alignment chart, the vertical axis S, the vertical axis CA, and the vertical axis R are axes respectively representing the rotational speed of the sun gear S0, the rotational speed of the carrier CA0, and the rotational speed of the ring gear R0. The distance between the axis CA and the vertical axis R is 1 when the distance between the vertical axis S and the vertical axis CA is 1. The distance between the vertical axis CA and the vertical axis R is ρ (the number of teeth Zs of the sun gear S0 / ring gear). R0 is set to be the number of teeth Zr). In such a power distributing mechanism 16, the output torque (engine torque) T _E of the engine 12 input to the carrier CA 0, the reaction torque by the first electric motor MG1 is input to the sun gear S0, the output element Since the torque larger than the torque input from the engine 12 appears in the ring gear R0, the first motor MG1 functions as a generator. That is, it has a power distribution mechanism 16 as a differential mechanism connected to the engine 12 so that power can be transmitted and a first electric motor MG1 as a differential motor connected so as to be able to transmit power to the power distribution mechanism 16. An electric continuously variable transmission 17 (see FIG. 1) is configured as an electric transmission mechanism in which the differential state of the power distribution mechanism 16 is controlled by controlling the operating state of the first electric motor MG1. That is, the electric continuously variable transmission 17 is operated as an electric continuously variable transmission by continuously changing the gear ratio. The power of the engine 12 is transmitted to the output shaft 14 through the electric transmission mechanism 17.

By differential state of the power distributing mechanism 16 is controlled, when the rotational speed (output shaft speed) N _OUT of the ring gear R0 is constant, the rotational speed of the first motor MG1 (first electric motor rotation speed) N _MG1 the varying vertically, continuously (steplessly) the rotational speed of the engine 12 (engine rotational speed) N _E can be changed. Broken line in FIG. 2 shows a state in which the engine rotational speed N _E is lowered when lowered from a value of a first electric motor rotation speed N _MG1 by the solid line. Further, by the power distributing mechanism 16 functions as the continuously variable transmission, for example, the operating point of the fuel economy best engine 12 (e.g., the operating point of the engine rotational speed N _E and the engine 12 defined by the engine torque T _E) The control to be set can be executed by controlling the first electric motor MG1. This type of hybrid type is called mechanical distribution type or split type.

  Returning to FIG. 1, the automatic transmission 18 includes, for example, a set of Ravigneaux type planetary gear mechanisms. That is, the first sun gear S1 and the second sun gear S2 are provided, and the short pinion P1 meshes with the first sun gear S1, and the short pinion P1 meshes with the long pinion P2 having a longer axial length, The long pinion P2 meshes with a ring gear R1 arranged concentrically with the sun gears S1 and S2. Each of the pinions P1 and P2 is held by a common carrier CA1 so as to rotate and revolve. Further, the second sun gear S2 meshes with the long pinion P2. The second sun gear S2 is connected to the second electric motor MG2, and the carrier CA1 is connected to the output shaft 14. The first sun gear S1 and the ring gear R1 constitute a mechanism corresponding to a tuple pinion type planetary gear device together with the pinions P1 and P2, and the second sun gear S2 and the ring gear R1 together with the long pinion P2 are single pinion type planetary gears. A mechanism corresponding to the apparatus is configured.

  The automatic transmission 18 also includes a first brake B1 provided between the first sun gear S1 and the housing 40, which is a non-rotating member, and a ring gear R1 in order to selectively fix the first sun gear S1. A second brake B2 provided between the ring gear R1 and the housing 40 is provided for selective fixing. These brakes B1 and B2 are so-called friction engagement devices that generate a braking force by a frictional force, and preferably a wet multi-plate type hydraulic friction in which a plurality of friction plates stacked on each other are pressed by a hydraulic actuator. It is constituted by an engagement device or the like, and is for selectively connecting members on both sides on which it is inserted. And it is comprised so that the torque capacity of brake B1, B2 may change continuously according to the hydraulic pressure (engagement pressure) of the hydraulic fluid for operating these brakes B1, B2.

  In the automatic transmission 18 configured as described above, the second sun gear S2 functions as an input rotating element (rotating member), the carrier CA1 functions as an output rotating element (rotating member), and the first brake B1 is engaged. When this is done, a high speed stage H with a gear ratio γsh greater than “1” is achieved. Further, when the second brake B2 is engaged instead of the first brake B1, the low speed stage L having a speed ratio γsl larger than the speed ratio γsh of the high speed stage H is set. As described above, the automatic transmission 18 establishes a shift stage by controlling supply and discharge of hydraulic oil to and from the hydraulic friction engagement device, that is, shifts by engagement and release of the hydraulic friction engagement device. This is a mechanical speed change mechanism capable of changing gears.

The shift between the gears H and L is executed based on the running state such as the vehicle speed and the required driving force related value (target driving force related value). More specifically, for example, a relationship obtained and set in advance having a shift line for selecting a gear position (shift diagram, shift map, see FIG. 10) is stored, and the detected running state is stored. Accordingly, control is performed so as to set one of the gear positions. The electronic control unit 150 is provided with a shift control electronic control unit (T-ECU) for performing the control. The shift control electronic control unit (T-ECU) includes an oil temperature sensor TS for detecting the temperature (hydraulic oil temperature) TH _{OIL of the} hydraulic oil, and an output rotational speed for detecting the output shaft rotational speed N _OUT. sensor NOS, detects the engine rotational speed sensor NES, the first electric motor rotational speed sensor NM1S, and the second electric motor rotation speed _{N MG2} for detecting a first electric motor speed _{N MG1} for detecting the engine rotational speed _{N E} For this purpose, a detection signal from the second motor rotation speed sensor NM2S or the like is supplied.

  The driving force-related value in the required driving force-related value corresponds to the driving force of the vehicle on a one-to-one basis, and includes not only the driving torque or driving force at the driving wheels 22 but also the output shaft 14 for example. Output torque (output shaft torque), engine torque, and vehicle acceleration. The required driving force related value is a required value (target value) of a driving force related value determined based on, for example, the accelerator opening (or throttle valve opening, intake air amount, air-fuel ratio, fuel injection amount). However, the accelerator opening or the like may be used as it is.

  FIG. 3 shows four vertical axes S1, vertical axes R1, vertical axes CA1, and CA1 in order to show the mutual relationship between the rotary elements (rotary members) of the Ravigneaux type planetary gear mechanism constituting the automatic transmission 18. An alignment chart having a vertical axis S2 is shown. The vertical axis S1, the vertical axis R1, the vertical axis CA1, and the vertical axis S2 indicate the rotational speed of the first sun gear S1, the rotational speed of the ring gear R1, the rotational speed of the carrier CA1, and the rotational speed of the second sun gear S2, respectively. Is. In the automatic transmission 18, when the ring gear R1 is fixed by the second brake B2, the low speed stage L is set, and the assist torque output from the second electric motor MG2 is amplified in accordance with the gear ratio γsl at that time and output shaft 14. Instead, when the first sun gear S1 is fixed by the first brake B1, the high speed stage H having a speed ratio γsh smaller than the speed ratio γsl of the low speed stage L is set. Since the gear ratio at the high speed stage H is also larger than “1”, the assist torque output from the second electric motor MG2 is increased according to the gear ratio γsh and added to the output shaft 14. In the state where the gears L and H are constantly set, the torque applied to the output shaft 14 is a torque obtained by increasing the output torque of the second electric motor MG2 in accordance with each gear ratio. In the transitional state of the automatic transmission 18, the torque is affected by the torque capacity at each brake B1, B2, the inertia torque accompanying the change in the rotational speed, and the like. The torque applied to the output shaft 14 is positive torque (drive torque) when the second electric motor MG2 is driven, and is negative torque (brake torque) when the second motor MG2 is driven. That is, in the driven state of the second electric motor MG2, a regenerative braking force is generated on the wheels 18 and 46 by the regenerative operation.

FIG. 4 shows a hydraulic pressure control circuit 50 for controlling the shift of the automatic transmission 18 by engaging and releasing the brakes B1 and B2. The hydraulic control circuit 50 includes a mechanical hydraulic pump 46 that is operatively connected to the crankshaft 36 of the engine 12 to be driven to rotate by the engine 12, a motor 48a, and a pump 48b that is driven to rotate by the motor 48a. The mechanical hydraulic pump 46 and the electric hydraulic pump 48 suck or return the working oil returned to the oil pan (not shown) via the strainer 52. The working oil directly refluxed through the oil passage 53 is sucked and pumped to the line pressure oil passage 54. Although the oil temperature sensor TS for detecting the recirculated hydraulic oil temperature TH _OIL is provided in the valve body 51 forming the hydraulic control circuit 50, it may be connected to another part.

  The line pressure regulating valve 56 is a relief type regulating valve, and is a spool valve element 60 that opens and closes between a supply port 56 a connected to the line pressure oil passage 54 and a discharge port 56 b connected to the drain oil passage 58. And a spring 62 for generating a thrust force in the valve closing direction of the spool valve element 60, and at the same time, when the set pressure of the line pressure PL is changed to a high value, the module pressure in the module pressure oil passage 66 is set via the electromagnetic on-off valve 64. A control oil chamber 68 for receiving PM, and a feedback oil chamber 70 connected to the line pressure oil passage 54 for generating thrust in the valve opening direction of the spool valve element 60, and one of two types of low pressure and high pressure A constant line pressure PL is output. The line pressure oil passage 54 is provided with a hydraulic switch SW3 that is turned on when the line pressure PL is a value on the high pressure side and turned off when the line pressure PL is equal to or less than the value on the low pressure side.

  The module pressure regulating valve 72 uses the line pressure PL as a source pressure, and a constant module pressure PM set lower than the line pressure PL on the low pressure side is supplied to the module pressure oil passage 66 regardless of the fluctuation of the line pressure PL. Output. The first linear solenoid valve SLB1 for controlling the first brake B1 and the second linear solenoid valve SLB2 for controlling the second brake B2 are command values from the electronic control unit 150 using the module pressure PM as a source pressure. Control pressures PC1 and PC2 corresponding to certain drive currents ISOL1 and ISOL2 are output.

  The first linear solenoid valve SLB1 has a normally open type valve characteristic that opens (communicates) between the input port and the output port when not energized, and increases the drive current ISOL1 as shown in FIG. Accordingly, the control pressure PC1 output is lowered. As shown in FIG. 5, the valve characteristic of the first linear solenoid valve SLB1 is provided with a dead zone A in which the control pressure PC1 output until the drive current ISOL1 exceeds a predetermined value Ia does not decrease. The second linear solenoid valve SLB2 has a normally closed valve characteristic that closes (shuts off) between the input port and the output port when the power is not supplied, and increases the drive current ISOL2 as shown in FIG. Along with this, the output control pressure PC2 is increased. As shown in FIG. 6, in the valve characteristic of the second linear solenoid valve SLB2, a dead zone B is provided in which the control pressure PC2 output until the drive current ISOL2 exceeds a predetermined value Ib does not increase.

  The B1 control valve 76 opens and closes the spool valve element 78 that opens and closes between the input port 76a connected to the line pressure oil passage 54 and the output port 76b that outputs the B1 engagement hydraulic pressure PB1. A control oil chamber 80 for receiving the control pressure PC1 from the first linear solenoid valve SLB1 and a spring 82 for biasing the spool valve element 78 in the valve closing direction are accommodated for biasing in the direction, and the output pressure is B1. A feedback oil chamber 84 for receiving the engagement hydraulic pressure PB1, and the B1 engagement hydraulic pressure having a magnitude corresponding to the control pressure PC1 from the first linear solenoid valve SLB1 using the line pressure PL in the line pressure oil passage 54 as a source pressure. PB1 is output and supplied to the brake B1 through the B1 apply control valve 86 that functions as an interlock valve.

  The B2 control valve 90 opens and closes the spool valve element 92 that opens and closes between the input port 90a connected to the line pressure oil passage 54 and the output port 90b that outputs the B2 engagement hydraulic pressure PB2. A control oil chamber 94 that receives the control pressure PC2 from the second linear solenoid valve SLB2 and a spring 96 that biases the spool valve element 92 in the valve closing direction are housed in order to urge the spool valve element 92 in the valve closing direction. A feedback oil chamber 98 for receiving the engagement hydraulic pressure PB2, and the B2 engagement hydraulic pressure having a magnitude corresponding to the control pressure PC2 from the second linear solenoid valve SLB2 using the line pressure PL in the line pressure oil passage 54 as a source pressure. PB2 is output and supplied to the brake B2 through the B2 apply control valve 100 that functions as an interlock valve.

  The B1 apply control valve 86 includes a spool valve element 102 that opens and closes between an input port 86a that receives the B1 engagement hydraulic pressure PB1 output from the B1 control valve 76 and an output port 86b that is connected to the first brake B1. An oil chamber 104 that receives the module pressure PM to urge the spool valve element 102 in the valve opening direction and a spring 106 that urges the spool valve element 102 in the valve closing direction are accommodated and output from the B2 control valve 90. And an oil chamber 108 that receives the B2 engagement hydraulic pressure PB2, and is opened until the B2 engagement hydraulic pressure PB2 for engaging the second brake B2 is supplied, but the B2 engagement hydraulic pressure PB2 Is switched to the closed valve state, and the engagement of the first brake B1 is blocked.

  The B1 apply control valve 86 is closed when the spool valve element 102 is in the valve open position (the position shown on the right side of the center line in FIG. 4), and conversely, the spool valve element 102 is closed. A pair of ports 110a and 110b are provided that are opened when they are at the position shown on the left side of the center line in FIG. A hydraulic switch SW2 for detecting the B2 engagement hydraulic pressure PB2 is connected to the one port 110a, and a second brake B2 is directly connected to the other port 110b. The hydraulic switch SW2 is configured to be turned on when the B2 engagement hydraulic pressure PB2 is in a preset high pressure state and switched to an off state when the B2 engagement hydraulic pressure PB2 is equal to or lower than a preset low pressure state. . Since the hydraulic switch SW2 is connected to the second brake B2 via the B1 apply control valve 86, the first linear solenoid valve constituting the hydraulic system of the first brake B1 simultaneously with the abnormality of the B2 engagement hydraulic pressure PB2. Abnormalities in the SLB1, B1 control valve 76, B1 apply control valve 86, etc. can also be determined.

  Similarly to the B1 apply control valve 86, the B2 apply control valve 100 also has a gap between the input port 100a that receives the B2 engagement hydraulic pressure PB2 output from the B2 control valve 90 and the output port 100b connected to the second brake B2. A spool valve element 112 that opens and closes, an oil chamber 114 that receives the module pressure PM to urge the spool valve element 112 in the valve opening direction, and a spring 116 that urges the spool valve element 112 in the valve closing direction are accommodated. And an oil chamber 118 that receives the B1 engagement hydraulic pressure PB1 output from the B1 control valve 76, and is kept open until the B1 engagement hydraulic pressure PB1 for engaging the first brake B1 is supplied. However, when the B1 engagement hydraulic pressure PB1 is supplied, the valve is switched to the closed state and the engagement of the second brake B2 is prevented. It is.

  The B2 apply control valve 100 is also closed when the spool valve element 112 is in the open position (the position shown on the right side of the center line in FIG. 4), and conversely, the spool valve element 112 is closed (see FIG. A pair of ports 120a and 120b are provided that are opened when they are at a position shown on the left side of the center line of FIG. A hydraulic switch SW1 for detecting the B1 engagement hydraulic pressure PB1 is connected to the one port 120a, and a first brake B1 is directly connected to the other port 120b. The hydraulic switch SW1 is configured to be turned on when the B1 engagement hydraulic pressure PB1 is in a preset high pressure state and switched to an off state when the B1 engagement hydraulic pressure PB1 is equal to or lower than a preset low pressure state. . Since this hydraulic switch SW1 is connected to the first brake B1 via the B2 apply control valve 100, the second linear solenoid valve constituting the hydraulic system of the second brake B2 simultaneously with the abnormality of the B1 engagement hydraulic pressure PB1. Abnormalities in the SLB2, B2 control valve 90, B2 apply control valve 100, etc. can also be determined.

  FIG. 7 is a chart for explaining the operation of the hydraulic control circuit 50 configured as described above. In FIG. 7, a circle indicates an excited state or an engaged state, and a cross indicates a non-excited state or a released state. That is, when the first linear solenoid valve SLB1 and the second linear solenoid valve SLB2 are both excited, the first brake B1 is disengaged and the second brake B2 is engaged, so that the automatic transmission 18 operates at a low speed. Stage L is achieved. On the other hand, the first linear solenoid valve SLB1 and the second linear solenoid valve SLB2 are both de-energized, whereby the first brake B1 is engaged and the second brake B2 is disengaged. High speed stage H is achieved.

  FIG. 8 is a functional block diagram illustrating a main part of a control function provided in the electronic control unit 150 in order to control the vehicle 8 (power transmission device 10). Note that the vehicle 8 is provided with a storage device 152 that stores a relationship used for control by such a control function.

  In FIG. 8, the hybrid drive control unit, that is, the hybrid drive control means 154 is activated by operating the power switch while the brake pedal 26 is operated after the key is inserted into a key slot (not shown), for example. Then, the driver's required output is calculated based on the accelerator operation amount, and the required output is generated from the engine 12 and / or the second electric motor MG2 so that the operation is low in fuel consumption and low in the amount of exhaust gas. For example, the engine 12 is stopped and the second motor MG2 is used as the driving source, and the power of the engine 12 is generated mechanically by the first motor MG1 using the power of the engine 12, and the power of the engine 12 is mechanically output to the output shaft 14 (drive wheels 22). ) In accordance with the driving state, such as an engine driving mode for driving and a driving mode in which the second electric motor MG2 is driven by the power generated by the first electric motor MG1 and torque is applied to the output shaft 14 in the engine driving mode. To make it happen.

The hybrid drive control means 154, when driving the engine 12, controls the engine rotational speed N _E by the first electric motor MG1 so that the engine 12 operates on the optimum fuel consumption curve, control the engine torque T _E To do. Further, when torque assist is performed by driving the second electric motor MG2, when the vehicle speed V is relatively slow, the automatic transmission 18 is set to the low speed stage L, the torque applied to the output shaft 14 is increased, and the vehicle speed is relatively low. In the increased state, the automatic transmission 18 is set to the high speed stage H, the rotational speed of the second electric motor MG2 is relatively lowered to reduce the loss, and efficient torque assist is executed. Further, when coasting, for example, the second electric motor MG <b> 2 is rotationally driven by inertial energy of the vehicle to regenerate electric power, and the electric power is stored in the power storage device 32.

  More specifically, the control in the engine travel mode will be described as an example. The hybrid drive control means 154 operates the engine 12 in an efficient operating range for the purpose of improving the power performance and the fuel efficiency. And the second motor MG2 are controlled so that the distribution of driving force and the reaction force generated by the first motor MG1 are optimized.

For example, the hybrid drive control means 154 determines a target drive force-related value such as a required output shaft torque T based on an accelerator opening or a vehicle speed as a driver output request amount from a drive force map stored in advance in the storage device 152 or the like. determining the _R, in consideration of the charging request value etc. from the required output shaft torque T _R to calculate the required output shaft power, transmission loss as its required output shaft power can be obtained, the auxiliary load, the second electric motor MG2 The target engine power P _E ^* is calculated in consideration of the assist torque of the automatic transmission 18 and the gear position of the automatic transmission 18. Then, the hybrid drive control means 154, for example, experimentally in advance as to achieve both drivability and fuel consumption in a two-dimensional coordinate composed of the engine rotational speed N _E and engine torque T _E as shown in FIG. 9 The operating point (operating point) of the engine 12, that is, the engine rotational speed at which the target engine power P _E ^* is obtained while operating the engine 12 along the engine optimal fuel consumption rate curve (fuel consumption map, relationship) calculated and stored in The engine 12 is controlled and the power generation amount of the first electric motor MG1 is controlled so that N _E and the engine torque T _E are obtained.

Optimum fuel consumption curve of the engine 12 shown by a broken line in FIG. 9 is previously experimentally determined is formed so as to pass with increasing engine rotational speed N _E of the lowest fuel consumption region in the iso-fuel consumption curve It is a curve connecting the optimum fuel consumption points. This optimum fuel consumption rate curve is also a series of points representing the minimum fuel consumption operating point of the engine 12 that has been experimentally set in advance so as to achieve both drivability and fuel efficiency. In addition, solid lines a, b, and c in FIG. 9 are examples representing the target engine power P _E ^*, and are also a series of points representing operating points of the engine 12 having the same engine power. The solid lines a, b, c The target engine power P _E ^* increases in the order of. For example, when the target engine power P _E ^* is increased from the solid line a shown in FIG. 9 to the solid line b, the target engine power P _E ^{* of the} solid line b is obtained, so that the engine 12 is pointed along the optimum fuel consumption rate curve. It is operated from A1 to point A2. That is, the raised first electric motor speed _{N MG1} example to increase the engine rotational speed _{N E} from NE1 to NE2, for example throttle control to raise the TE1 the engine torque _{T E} to TE2, the fuel injection control, Ignition timing control is performed.

  The hybrid drive control means 154 performs control to supply the electric energy generated by the first electric motor MG1 to the power storage device 32 and the second electric motor MG2 via the inverters 28 and 30. The main part of the motive power of the engine 12 is mechanically transmitted to the output shaft 14, but a part of the motive power of the engine 12 is consumed for power generation of the first electric motor MG1, and is converted into electric energy there. , 30 and the electric energy is supplied to the second electric motor MG2, and the second electric motor MG2 is driven as the electric motor by the electric energy, so that the power output from the second electric motor MG2 is automatically transmitted. It is transmitted to the output shaft 14 via 18. An electric path from conversion of part of the power of the engine 12 to electric energy and conversion of the electric energy into mechanical energy by a device related to the generation of the electric energy until it is consumed in the second electric motor MG2 Composed. The hybrid drive control means 154 supplies electric energy directly from the power storage device 32 via the inverter 30 to the second electric motor MG2 in addition to the electric energy by the electric path to drive the second electric motor MG2. Is possible.

The hybrid drive control means 154, regardless of the stopping or during traveling of the vehicle, or to maintain the engine speed N _E substantially constant by controlling the first electric motor MG1 by the differential action of the power distributing mechanism 16 It can be controlled to an arbitrary rotational speed. In other words, the hybrid drive control unit 154 is capable of rotation control of the first electric motor MG1 into any rotational speed while controlling the engine rotational speed N _E to any rotational speed or maintained substantially constant.

  The hybrid drive control means 154 controls opening / closing of the electronic throttle valve by a throttle actuator for throttle control, controls the fuel injection amount and injection timing by the fuel injection device for fuel injection control, and controls ignition timing. For this purpose, a command for controlling the ignition timing by an ignition device such as an igniter is output alone or in combination to an engine output control device (not shown), and output control of the engine 12 is executed so as to generate necessary engine output. The engine output control means is functionally provided.

Returning to FIG. 8, the shift control unit, that is, the shift control unit 156 determines a shift operation in the automatic transmission 18 and executes the determined shift operation. For example, the speed change control means 156 can obtain a vehicle speed V (output shaft rotational speed N _OUT ) and a required driving force (for example, stored in advance) from a speed change diagram (speed change map) as shown in FIG. The shift of the automatic transmission 18 is determined based on the required output shaft torque T _R ) determined by the hybrid drive control means 154 based on the accelerator operation amount, the vehicle speed, etc. Shift processing for controlling the first brake B1 and the second brake B2 is performed so as to switch to the gear position.

  For example, when the shift control means 156 determines a shift operation from the low speed stage L to the high speed stage H, the shift control means 156 engages the first brake B1 and releases the second brake B2 via the hydraulic control circuit 50. The hydraulic actuators for the brakes B1 and B2 are controlled. Further, when a shift operation from the high speed stage H to the low speed stage L is determined, the first brake B1 is released and the second brake B2 is engaged via the hydraulic control circuit 50. Control the hydraulic actuator. For example, a so-called clutch-to-clutch shift is performed in both the shift operation from the low speed stage L to the high speed stage H and the shift operation from the high speed stage H to the low speed stage L.

  In the shift diagram shown in FIG. 10, the solid line is an upshift line (up line) for switching from the low speed stage L to the high speed stage H, and the broken line is a downshift line (down line) for switching from the high speed stage H to the low speed stage L. A predetermined hysteresis is provided between the upshift line and the downshift line. The shift diagram shown in FIG. 10 can be driven at a gear stage that can drive the vehicle 8 in a state with good fuel efficiency while drawing out the performance of the vehicle 8, that is, the fuel efficiency and the driving performance (power performance) are compatible. As described above, it is obtained experimentally in advance and stored in the storage device 152. That is, the shift map shown in FIG. 10 is a shift map A having shift lines (upshift line and downshift line) set in advance so that an optimal shift stage that achieves both fuel efficiency and power performance is selected. It is. In this way, the automatic transmission 18 is established with the optimum gear stage by controlling the supply and discharge of hydraulic oil to and from the hydraulic friction engagement devices (brakes B1 and B2) according to the shift map A.

Here, for example, the hydraulic oil in the hydraulic control circuit 50 is agitated by a rotary member (rotary element, rotary member) constituting the power transmission device 10 (for example, agitation by a rotary member half-immersed in the hydraulic oil in the housing 40). Air may get mixed in. Then, when a shift of the automatic transmission 18 is executed in a state where air is mixed in the hydraulic oil, for example, a desired engagement transient hydraulic pressure for controlling the engagement-side hydraulic friction engagement device toward engagement is obtained. This may cause an increase in shift shock. On the other hand, in the power transmission device 10 of the present embodiment, the other rotation speed can be controlled independently regardless of one rotation speed, and the contribution of the hydraulic control circuit 50 to the mixing of air with the hydraulic oil is different 2 There are two rotating elements (rotating members). For example, in the power transmission device 10 of the present embodiment, the engine rotation speed _NE and the second motor rotation speed _NMG2 can be independently controlled regardless of one rotation speed. Further, as shown in FIGS. 11 and 12, foamed rate of the hydraulic oil is changed by each of the change in the rotational speed of the engine rotational speed N _E and the second electric motor rotation speed N _MG2. That is, the respective rotation speeds of the engine rotation speed _NE and the second motor rotation speed _NMG2 contribute to the air mixing. Thus, the two as the rotating member, for example, the engine rotational speed N rotating element e.g. carrier CA0 of the power distribution mechanism 16 which is rotationally driven by the engine 12 in one-to-one correspondence with the _E, and the second electric motor rotation speed N _MG2 The rotating element of the automatic transmission 18 that is rotationally driven by the second electric motor MG2 in a one-to-one relationship, for example, the second sun gear S2. The rotation speeds of the two rotating members are the engine rotation speed _NE and the second motor rotation speed _NMG2 .

As described above, in the power transmission device 10 of the present embodiment, the rotational drive of the engine 12 and the rotational drive of the second electric motor MG2 that are factors that cause air to be mixed into the hydraulic oil, that is, factors that affect foaming (stirring) of the hydraulic oil. There are controlled each independently, for example, those stirring state of the hydraulic oil varies for the combination of the control, the rotational speed and air of each of the engine rotational speed N _E and the second electric motor rotation speed N _MG2 in other perspectives Since the degree of contribution to mixing is different, there is a possibility that the air mixing progress (air mixing progress) cannot be accurately estimated (determined) from the rotational speed of a certain rotating member. For this reason, for example, there is a possibility that an appropriate measure cannot be executed with respect to air contamination in the hydraulic oil.

Therefore, in the present embodiment, the degree of air mixing in the hydraulic oil is calculated based on the engine rotation speed _NE and the second motor rotation speed _NMG2 . Specifically, the storage device 152 is obtained and set in advance for calculating the degree of air contamination in the hydraulic oil per unit time based on, for example, the engine rotation speed _NE and the second motor rotation speed _NMG2. The relationship (foam content estimation map) is stored. FIG. 13 is a diagram (table) showing an example of the foam content estimation map. 13, the foamed amount estimation map, for example, FIG. 11 and as is apparent from the characteristic diagram of the hydraulic oil foamed rate for each rotational speed shown in FIG. 12, the higher the engine rotational speed N _E, the air The mixing degree is set so as to increase, and the higher the second motor rotation speed _NMG2 , the higher the air mixing degree. Moreover, FIG.13 (b) represents the relationship shown to Fig.13 (a) in another form, and is the substantially same foam content estimation map. In FIG. 13 (b), the engine rotational speed _NE is used as a parameter, and the second motor rotational speed _NMG2 and the air mixing degree per unit time are mapped as a relationship that is experimentally obtained and set in advance. . Then, sequentially calculates the air intrusion degree of the working fluid per unit time based on the foamed volume engine from estimation map rotational speed N _E and the second electric motor rotation speed N _MG2 shown in FIG. 13, the air mixing degree Is counted, and the progress of air mixing in the hydraulic oil is sequentially calculated. The unit time may be, for example, a cycle time in a flowchart (FIG. 15) illustrating a control operation of the electronic control device 150 described later, or may be a predetermined time such as 1 second or 1 minute. . Accordingly, it goes without saying that the foam content estimation map is set in accordance with the set unit time.

  More specifically, referring back to FIG. 8, the traveling state determination unit, that is, the traveling state determination unit 158 determines whether the vehicle 8 is traveling in low gear, for example, whether the shift stage of the automatic transmission 18 is the low speed L. It is determined whether or not. For example, the traveling state determination unit 158 determines whether or not the shift stage of the automatic transmission 18 is set to the low speed stage L based on the control state of the hydraulic actuator via the hydraulic control circuit 50 by the shift control unit 156. To do.

The air mixing progress degree calculating unit, that is, the air mixing progress degree calculating means 160 is, for example, shown in FIG. 13 when the traveling state determining means 158 determines that the gear position of the automatic transmission 18 is the low speed stage L. successively calculating the air-containing degree of the working fluid per unit time based from foamed amount estimation map as shown in the engine rotational speed N _E and the second electric motor rotation speed N _MG2. Next, the air mixing progress degree calculating means 160 counts (counts up) the air mixing degree, and sequentially calculates the counting result as the air mixing progress degree in the hydraulic oil.

  The air mixing progress degree determination unit, that is, the air mixing progress degree determination means 162 is, for example, a predetermined value that is set by experimentally obtaining in advance the air mixing progress degree in the hydraulic oil that is sequentially calculated by the air mixing progress degree calculating means 160. It is determined whether or not the number is exceeded.

The shift control means 156 changes the hydraulic control related to the shift of the automatic transmission 18 when the air mixing progress degree determination means 162 determines that the air mixing progress degree exceeds a predetermined value. For example, the shift control means 156 compares at least the upshift line in the shift map A as shown in FIG. 10 with the upshift line of the shift map A and selects the high gear ratio side (that is, the high speed stage H). It is changed to a preset upshift line so that it can be easily performed, that is, the upshift is accelerated. This is because the effect of foaming (stirring) of hydraulic oil due to the rotational drive of the second electric motor MG2 is suppressed by upshifting relatively early and lowering the second motor rotation speed _NMG2 , that is, generation of bubbles. This improves the discharge probability of air in the hydraulic oil. Accordingly, the predetermined value is experimentally obtained and set in advance as, for example, a value before the value of the degree of air mixing progressing so as to affect the speed change operation of the automatic transmission 18 due to air mixing in the hydraulic oil. The judgment value.

  FIG. 14 shows an air suppression upshift line (changed so that the high-speed stage H can be easily selected by comparing only the upshift line (solid line) of the shift map A shown in FIG. 10 with the upshift line of the shift map A. This is a shift map B obtained experimentally in advance and stored in the storage device 152 having a two-dot chain line). As shown in FIG. 14, the air suppression upshift line (two-dot chain line) is, for example, in a region where the vehicle speed V is lower and the required driving force is higher than the upshift line (solid line) of the shift map A. The upshift line of the shift map A is shifted to the left side (low vehicle speed side) so that the high speed stage H on the high vehicle speed side (high gear side) is selected in the high region, that is, the upshift is judged earlier. Is set in advance.

  That is, the shift control means 156 performs a shift according to the shift map A as shown in FIG. 10 when the air mixing progress degree determination means 162 determines that the air mixing progress degree has not yet exceeded the predetermined value. . On the other hand, the shift control means 156 executes a shift according to a shift map B as shown in FIG. 14 when the air mixing progress degree determining means 162 determines that the air mixing progress degree exceeds a predetermined value.

  FIG. 15 is a view for accurately calculating the progress of air mixing in the hydraulic oil so that an appropriate measure can be executed for the main part of the control operation of the electronic control unit 150, that is, air mixing in the hydraulic oil. This is a flowchart for explaining the control operation, and is repeatedly executed with an extremely short cycle time of about several milliseconds to several tens of milliseconds, for example. FIG. 16 is a time chart when the control operation shown in the flowchart of FIG. 15 is executed.

In FIG. 15, first, in step (hereinafter, step is omitted) S10 corresponding to the traveling state determination means 158, for example, whether or not the vehicle 8 is traveling in low gear, that is, the gear position of the automatic transmission 18 is low. It is determined whether or not the level is L. If the determination in S10 is negative, this routine is terminated. If the determination is affirmative, in S20 corresponding to the air mixing progress degree calculation means 160, for example, the engine rotation is calculated from the foam content estimation map as shown in FIG. Based on the speed _NE and the second motor rotation speed _NMG2 , the degree of air mixing in the hydraulic oil per unit time is calculated. Next, in S30 corresponding to the air mixing progress degree calculation means 160, for example, the air mixing degree calculated in S20 is counted (counted up), and the counting result is calculated as the air mixing progress degree in the hydraulic oil. The Next, in S40 corresponding to the air mixing progress determination means 162, for example, it is determined whether or not the air mixing progress in the hydraulic oil calculated in S30 has exceeded a predetermined value. If the determination in S40 is affirmative, a shift map B as shown in FIG. 14 is set as a shift map used for shifting of the automatic transmission 16, for example, in S50 corresponding to the shift control means 156. Shifting is performed. On the other hand, if the determination in S40 is negative, in S60 corresponding to the shift control means 156, a shift map A as shown in FIG. 10 is set as a shift map used for shifting of the automatic transmission 16, for example. Shifting is performed according to map A.

In FIG. 16, the solid line shows the present embodiment in which the upshift is executed when the shift map is switched between the shift map A and the shift map B in accordance with the appropriately calculated degree of air mixing in the hydraulic fluid. The broken line shows a conventional example in which the upshift is executed when the shift map A is always used or when the air mixing progress in the hydraulic oil is not accurately calculated. In the conventional example shown in broken lines, the response delay of the first brake B1 to the engagement transition oil pressure when engaging is generated by air contamination, the second electric motor rotation speed N _MG2 is racing during shifting transition, the vehicle acceleration G Depression has occurred and shift shock has increased. In contrast, in the present embodiment shown in solid line, the desired engagement transition oil pressure obtained when engaging the first brake B1, racing and vehicle acceleration of the second electric motor rotation speed N _MG2 during the shift transient The drop of G is reliably suppressed, and the shift shock is suppressed. The fact that a desired engagement transient oil pressure can be obtained means that the actual engagement transient oil pressure changes as assumed, for example, with respect to the engagement transient oil pressure command value obtained and set in advance. .

As described above, according to the present embodiment, for example, the rotational speed (engine rotational speed N) of each of the two rotating members having different contributions to the air mixing into the hydraulic oil from the foam content estimation map as shown in FIG. _E and the second motor rotation speed N _MG2 ), the air mixing degree in the hydraulic oil per unit time is sequentially calculated, and the air mixing degree in the hydraulic oil is counted by counting (counting up). Since the degrees are sequentially calculated, in the power transmission device 10 in which the rotational driving of the two rotating members can be controlled independently, the degree of air mixing in the hydraulic oil involved in the shift of the automatic transmission 18 is accurately calculated. (Estimated). As a result, for example, it is possible to execute an appropriate measure against air mixing in the hydraulic oil, such as changing the hydraulic control related to the shift of the automatic transmission 10.

  Further, according to the present embodiment, when the sequentially calculated degree of air mixing exceeds a predetermined value, the hydraulic control related to the shift of the automatic transmission 18 is changed. It is possible to easily discharge air from the hydraulic oil according to the progress of air mixing in the hydraulic oil to be performed, and to suppress an increase in shift shock.

Further, according to the present embodiment, the high gear ratio side selects the upshift line of the shift map A as shown in FIG. 10 that is set in advance so as to select the optimum gear position as compared with the upshift line. Since the hydraulic control related to the shift of the automatic transmission 18 is changed by changing to the upshift line of the shift map B as shown in FIG. 14 set in advance so as to be easily performed, for example, the degree of progress of air mixing in the hydraulic oil is changed. When the engine speed exceeds a predetermined value, the automatic transmission 18 is easily upshifted, and the agitation of the hydraulic oil is reduced due to a decrease in the second motor rotation speed _NMG2 due to the upshift of the automatic transmission 18. It becomes easy to discharge air from oil. In other words, the upshift can be performed early before the shift shock worsens, and the shift shock during the actual upshift is appropriately suppressed.

  Further, according to the present embodiment, the two rotating members are the rotation elements of the power distribution mechanism 16 that is rotationally driven by the engine 12, such as the carrier CA0, and the rotation of the automatic transmission 18 that is rotationally driven by the second electric motor MG2. Since the element is, for example, the second sun gear S2, a foam content estimation map as shown in FIG. 13 for calculating the degree of air contamination in the hydraulic oil per unit time is appropriately set, and the foam content estimation is performed. From the map, the air mixing degree is appropriately calculated based on the rotational speeds of the two rotating members. And the air mixing progress degree in hydraulic fluid is calculated appropriately by counting the air mixing degree.

Further, according to the present embodiment, the rotational speeds of the two rotating members are the engine rotational speed _NE and the second electric motor rotational speed N _MG2 , so the engine rotational speed _NE and the second electric motor rotational speed N For example, a foam amount estimation map as shown in FIG. 13 for calculating the degree of air contamination in the hydraulic oil per unit time based on _MG2 is appropriately set, and the engine speed N is calculated from the foam amount estimation map. _The air mixing degree is appropriately calculated based on _E and the second motor rotation speed _NMG2 . And the air mixing progress degree in hydraulic fluid is calculated appropriately by counting the air mixing degree.

Further, according to this embodiment, foamed amount estimation map shown in FIG. 13 for example for calculating the air intrusion degree, the higher the engine rotational speed N _E, set to air intrusion degree increases The higher the second motor rotation speed N _MG2 is, the higher the air mixing degree is, so that the hydraulic oil per unit time is based on the engine rotation speed _NE and the second motor rotation speed N _MG2. For example, a foam amount estimation map as shown in FIG. 13 for calculating the air mixing degree is more appropriately provided.

  Next, another embodiment of the present invention will be described. In the following description, parts common to the embodiments are denoted by the same reference numerals and description thereof is omitted.

In the above-described embodiment, FIG. 10 is set in advance so that an optimal shift stage is selected as a mode of changing the hydraulic control related to the shift of the automatic transmission 18 when the air mixing progress exceeds a predetermined value. The upshift line of the shift map A as shown is changed to an upshift line set in advance so that the high speed stage H can be easily selected as compared with the upshift line of the shift map A. In the present embodiment, as another aspect of changing the hydraulic control related to the shift of the automatic transmission 18 when the air mixing progress exceeds a predetermined value, the air mixing in the hydraulic oil during the shift transition of the automatic transmission 18 is performed. It is proposed to delay the lowering of the hydraulic pressure of the release-side hydraulic friction engagement device so as to compensate for the increase delay of the actual hydraulic pressure of the engagement-side hydraulic friction engagement device due to the above. This is because, when engaging the hydraulic friction engagement device on the engagement side during the shift transition of the automatic transmission 18, a desired engagement transient hydraulic pressure cannot be obtained due to air mixing in the hydraulic oil, and the second electric motor against the drop or the like of the racing and vehicle acceleration G of the rotational speed N _MG2 occurs by delaying a decrease of disengagement transition pressure of hydraulic friction engagement devices only release side correspondingly delayed rise of engagement transition oil pressure, This _prevents the second motor rotation speed _NMG2 from being blown up. Therefore, the predetermined value in the present embodiment is experimentally obtained and set in advance as a value of the degree of air mixing progress that affects the speed change operation of the automatic transmission 18 due to air mixing in the hydraulic oil, for example. It is a judgment value.

Specifically, returning to FIG. 8, the shift control means 156 determines that the air mixing progress degree exceeds a predetermined value by the air mixing progress degree determination means 162 instead of changing the shift map in the above-described embodiment. In this case, for example, when the first brake B1 is engaged and the second brake B2 is released at the time of upshifting, the release is performed when the second brake B2 is obtained and set in advance in the clutch-to-clutch shift when releasing the second brake B2. By delaying the start timing of the sweep down (hydraulic pressure gradual reduction command) at the transient hydraulic pressure command value by a predetermined time, the hydraulic control related to the shift of the automatic transmission 18 is changed. The predetermined time is a predetermined time which is set previously obtained experimentally for racing or the like of the second electric motor rotation speed N _MG2 is suppressed. It should be noted that the predetermined time may not be used as the predetermined time, and the predetermined time may be set longer as the degree of air mixing progress increases. Thus, racing, etc. of the second electric motor rotation speed N _MG2 is suppressed even more appropriately.

  FIG. 17 is a diagram for accurately calculating the progress of air mixing in the hydraulic oil so that an appropriate measure can be executed for the main part of the control operation of the electronic control unit 150, that is, air mixing in the hydraulic oil. This is a flowchart for explaining the control operation, and is repeatedly executed with an extremely short cycle time of about several milliseconds to several tens of milliseconds, for example. The flowchart of FIG. 17 is another embodiment corresponding to the flowchart of FIG. 15, and is mainly different in that steps S50 and S60 in FIG. 15 are steps S50 'and S60'. Accordingly, in the description of the flowchart of FIG. FIG. 18 is a time chart when the control operation shown in the flowchart of FIG. 17 is executed.

  In FIG. 17, when the determination in S40 is affirmative, in S50 ′ corresponding to the shift control means 156, for example, when an upshift of the automatic transmission 16 is executed, the release transient hydraulic pressure command value for the second brake B2 is set. The start timing of the sweep down (hydraulic pressure gradually decreasing command) is delayed by a predetermined time. On the other hand, if the determination in S40 is negative, in S60 ′ corresponding to the shift control means 156, for example, when an upshift of the automatic transmission 16 is executed, it is obtained in advance in clutch-to-clutch shift. The normal shift control is executed with the shift hydraulic pressure command value set (the release transient hydraulic pressure command value when releasing the second brake B2 and the engagement transient hydraulic pressure when engaging the first brake B1).

In FIG. 18, the solid line shows the present embodiment when the release transient hydraulic pressure command value of the second brake B2 at the time of upshift is changed in accordance with the appropriately calculated degree of air mixing in the hydraulic oil. The broken line shows that the degree of progress of air mixing in the hydraulic oil was not accurately calculated, so that the release transient hydraulic pressure command value of the second brake B2 at the time of upshift was not changed even though the degree of air mixing progress was large. The conventional example of the case is shown. In the conventional example shown by the broken line, due to the occurrence of response delay of the engagement transient hydraulic pressure of the first brake B1 due to air mixing, the second motor rotation speed _NMG2 blows up during the shift transition, and the vehicle acceleration G falls. Shift shock is increasing. On the other hand, in the present embodiment shown by the solid line, the decrease in the release transient hydraulic pressure of the second brake B2 is delayed so as to compensate for the response delay (rise delay) of the engagement transient hydraulic pressure of the first brake B1, so During the transition, the second motor rotation speed _NMG2 is blown up and the vehicle acceleration G is reliably suppressed, and the shift shock is suppressed.

As described above, according to the present embodiment, when the automatic transmission 18 is upshifted, the second brake B2 is compensated for the increase delay in the engagement transient hydraulic pressure due to air mixing when the first brake B1 is engaged. Since the hydraulic control related to the shift of the automatic transmission 18 is changed by delaying the decrease in the release transient hydraulic pressure when releasing the engine, for example, when the degree of air mixing in the hydraulic oil exceeds a predetermined value, the shift is performed. The decrease in the release side hydraulic pressure in the transient process (upshift process) is easily delayed, and the increase (blowing) of the second motor rotation speed _NMG2 in the shift transient process is easily suppressed. That is, for example, even when the degree of air mixing in the hydraulic oil exceeds a predetermined value, the shift shock at the actual shift (upshift) is appropriately suppressed.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

For example, in the above-described embodiment, as the two rotating members, for example, the carrier CA0 that is rotationally driven by the engine 12 and the second sun gear S2 that is rotationally driven by the second electric motor MG2 are illustrated, but the present invention is not necessarily limited thereto. . In short, the present invention can be applied to any two rotating members whose rotation speeds can be controlled independently and have different degrees of contribution to air mixing into the hydraulic oil. For example, when one rotating member is a rotating element of the automatic transmission 18 that is driven to rotate by the second electric motor _MG2 in a one-to-one correspondence with the second electric motor rotational speed _NMG2 , the other rotating member is the second electric motor. A power distribution mechanism that is driven to rotate by the first motor _MG1 in a one-to-one correspondence with the first motor rotation speed N _MG1 independently of the rotation speed N _MG2 (that is, regardless of the change in the second motor rotation speed N _MG2 ). There may be 16 rotation elements such as the sun gear S0. In such a case, the rotation speeds of the two rotating members are, for example, the second motor rotation speed N _MG2 and the first motor rotation speed N _MG1 , and the second motor rotation speed N _MG2 and the first motor rotation speed. foamed amount estimation map shown in FIG. 13 is set to N _MG1 based. For example, when one of the rotary member is a rotary element of the power distribution mechanism 16 which is rotationally driven by the engine 12 in one-to-one correspondence with the engine rotational speed N _E, the other rotating member is the engine rotational speed N _E there independently (i.e. regardless of the change in the engine rotational speed N _E) in such rotating element e.g. carrier CA1 of the automatic transmission 18 corresponding to the one-to-one to the second electric motor rotation speed N _MG2 (i.e., the output shaft 14) and It ’s fine. In such a case, the rotational speeds of the two rotating members are, for example, the engine rotational speed _NE and the output shaft rotational speed N _OUT (= second electric motor rotational speed N _MG2 / speed ratio γs of the automatic transmission 18). , and the foamed amount estimation map shown in FIG. 13 on the basis of the engine rotational speed N _E and the output shaft rotation speed N _OUT is set. Even if it does in this way, the same effect is acquired.

  In the second embodiment, the upshift is exemplified as the shift control of the automatic transmission 18, but the present invention can be applied to a downshift. Specifically, when the air mixing progress degree determination means 162 determines that the air mixing progress degree has exceeded a predetermined value, the shift control means 156 engages the second brake B2 during the downshift, for example. The start time of the sweep-down (hydraulic pressure gradual reduction command) at the release transient hydraulic pressure command value when releasing the first brake B1 that is obtained and set in advance in the clutch-to-clutch shift when releasing one brake B1 is a predetermined time. The hydraulic control related to the shift of the automatic transmission 18 is changed by delaying only by the delay. Even if it does in this way, the same effect is acquired. In this case, step S10 in the flowchart of FIG. 17 is not necessary.

  In the above-described embodiment, the automatic transmission 18 is provided between the second electric motor MG2 and the output shaft 14 so that the torque output from the second electric motor MG2 is increased and added to the output shaft 14. The two-stage automatic transmission (reduction gear) having the low speed stage L and the high speed stage H is not limited to the automatic transmission 18, but the torque output from the second electric motor MG <b> 2 is transmitted to the output shaft 14. Thus, the present invention can be applied to any automatic transmission provided between the second electric motor MG2 and the output shaft 14. For example, in a planetary gear type multi-stage transmission having three or more speed stages, a stepped automatic transmission in which the torque output by MG2 is increased and added to the output shaft 14 in some or all of the speed stages, etc. There may be. Further, when a planetary gear type multi-stage transmission having three or more speed stages is adopted, whether or not the vehicle is traveling at a gear stage excluding, for example, the highest gear ratio in step S10 in the flowchart of FIG. Is determined.

  In the above-described embodiment, the electric continuously variable transmission 17 is an electric transmission mechanism that is operated as an electric continuously variable transmission by continuously changing its gear ratio. In addition to operating as a continuously variable transmission, it is also possible to operate as a stepped transmission by changing the gear ratio stepwise.

  In the above-described embodiment, the power distribution mechanism 16 is a single planetary, but may be a double planetary. The power distribution mechanism 16 is a differential gear device in which, for example, a pinion rotated by the engine 12 and a pair of bevel gears meshing with the pinion are operatively connected to the first electric motor M1 and the output shaft 14. Also good.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Vehicle power transmission device 12: Engine 14: Output shaft 16: Power distribution mechanism (differential mechanism)
17: Electric continuously variable transmission (electric transmission mechanism)
18: Automatic transmission (mechanical transmission mechanism)
150: Electronic control device (control device)
B1: First brake (hydraulic friction engagement device)
B2: Second brake (hydraulic friction engagement device)
CA0: Carrier (Rotating member of differential mechanism)
S2: Second sun gear (rotary member of automatic transmission)
MG1: First motor (differential motor)
MG2: Second electric motor (traveling motor)

Claims (7)

The differential mechanism is connected to the engine so as to be capable of transmitting power, and the differential motor is connected to the differential mechanism so as to be capable of transmitting power. An electric transmission mechanism in which a differential state of the dynamic mechanism is controlled, an automatic transmission in which a gear stage is established by controlling supply and discharge of hydraulic oil to and from the hydraulic friction engagement device, and the electric transmission mechanism A vehicle power transmission control device comprising: a traveling motor coupled to the output shaft of the power transmission through the automatic transmission so as to be capable of transmitting power;
In order to calculate the degree of air mixing in the hydraulic oil per unit time based on the rotational speed of each of the two rotating members whose rotation speed can be controlled independently and the contribution to the air is different. With preset relationships,
From the relationship, the air mixing degree per unit time is sequentially calculated based on the rotation speed of each of the two rotating members,
A control device for a vehicle power transmission device, wherein the degree of air mixing in the hydraulic oil is sequentially calculated by counting the degree of air mixing.   2. The control device for a vehicle power transmission device according to claim 1, wherein when the sequentially calculated degree of progress of air mixing exceeds a predetermined value, hydraulic control related to shifting of the automatic transmission is changed. . In the automatic transmission, the optimum shift speed is established by controlling the supply and discharge of hydraulic oil to and from the hydraulic friction engagement device according to a preset shift line so that the optimum shift speed is selected. Is what
At least an upshift line among the preset shift lines so that the optimum gear position is selected is changed to a preset upshift line so that the high gear ratio side can be selected more easily than the upshift line. The control device for a vehicle power transmission device according to claim 2, wherein the hydraulic control related to the shift of the automatic transmission is changed by changing. The automatic transmission is a mechanical transmission mechanism in which a gear position is switched by engagement and release of the hydraulic friction engagement device,
The automatic transmission shifts by delaying the decrease in the hydraulic pressure of the release-side hydraulic friction engagement device so as to compensate for the delay in the increase of the hydraulic pressure of the engagement-side hydraulic friction engagement device due to air mixing. The control device for a vehicle power transmission device according to claim 2, wherein the hydraulic control for the vehicle is changed.   The two rotating members are a rotating member of the differential mechanism that is driven to rotate by the engine and a rotating member of the automatic transmission that is driven to rotate by the electric motor for traveling. 5. The control device for a vehicle power transmission device according to any one of 4 above.   6. The vehicle power transmission device according to claim 1, wherein the rotation speed of each of the two rotation members is a rotation speed of the engine and a rotation speed of the electric motor for traveling. 6. Control device.   The preset relationship for calculating the air mixing degree is set such that the air mixing degree increases as the rotational speed of the engine increases, and the air rotating degree increases as the rotational speed of the electric motor for traveling increases. The control device for a vehicle power transmission device according to claim 6, wherein the control device is set to increase the degree of mixing.

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