JP2017071322A - Control apparatus for hybrid-vehicular drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control apparatus for a hybrid-vehicular drive device, the control apparatus for securing a lubrication oil supply volume to a bearing that rotatably supports a counter-gear mechanism.SOLUTION: An engine revolution speed control part sets a revolution speed Ne of an engine 14 higher when an accelerator is off with a low oil temperature as compared to the case of an accelerator-off travel with a high oil temperature, thus increasing a discharge amount from an oil pump 38 and suppressing a failure in lubricating a bearing 26s that rotatably supports a counter-gear mechanism 26. Further, cancelling-normal torque is output from a second motor MG 2, the torque cancelling at least a portion of friction torque of a non-operation engine 14 generated by increasing the engine revolution speed Ne, and therefore it is possible to suppress a thrust load to the bearing from increasing as a result of driven torque increasing.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a control device for a hybrid vehicle drive device having a counter gear mechanism that meshes with an output gear of a power distribution mechanism and a second electric motor, and more particularly to a lubrication technique at a low oil temperature.

  One type of hybrid vehicle drive device includes an engine, a first electric motor, a first rotating element connected to the engine, a second rotating element connected to the first electric motor, and a third rotating element connected to an output gear. And a counter gear mechanism that meshes with the second electric motor, the output gear, and the diff ring gear of the differential gear device. For example, this is the hybrid vehicle drive device described in Patent Document 1.

  In the hybrid vehicle drive apparatus of the above type, the engine and the first electric motor are provided rotatably on the first axis, the second electric motor is provided rotatably on the third axis, and the counter gear mechanism counter Since the shaft is rotatably provided on the second axis and the differential gear device is rotatably provided on the fourth axis, it is referred to as a motor double-shaft transaxle or a four-shaft transaxle. In such a type of transaxle, the first axis, the second axis, and the fourth axis parallel to each other are set at a relatively low position, and the third axis is in the vertical direction of the fourth axis. It is set to the highest position above, and the first axis is connected to the third axis and the fourth axis at the intermediate height position between the third axis and the fourth axis on the side of the line, and the second axis The axis is set at a position surrounded by the first axis, the third axis, and the fourth axis.

  The counter gear mechanism of the hybrid vehicle drive device disclosed in Patent Document 1 includes a counter shaft that is rotatably arranged on a third axis, and an output gear (on the first shaft that is provided on the counter shaft). Counter drive gear) and a counter driven gear meshed with the output gear of the second electric motor provided on the second axis, and a differential drive provided on the counter shaft and meshed with a diff ring gear on the fourth axis It is comprised by providing with a gear.

JP 2013-166548 A

  In the hybrid vehicle drive device configured as described above, the bearing that rotatably supports the countershaft is lubricated by the lubricating oil scooped up by the ring gear of the differential gear device. There wasn't. That is, it is difficult to directly supply the lubricating oil scraped up by the diff ring gear to the counter shaft on the third axis sandwiched between the first axis and the second axis. Since the diff ring gear is supplied to the output gear (counter drive gear) and the lubricating oil is scraped up by the counter driven gear and supplied to the bearing that rotatably supports the counter shaft, stable lubrication is difficult. In a low oil temperature state where the viscosity of the lubricating oil is high, there is a problem that the supply amount of the lubricating oil cannot be further obtained. In particular, among the bearings that rotatably support the counter shaft, the bearing that supports the shaft end on the side away from the differential drive gear is separated from the differential drive gear, which is the site where the lubricant is scraped. It was disadvantageous to oil. Further, when the vehicle is driven, a load in the thrust direction due to the torsion angle of the counter driven gear is applied to the bearing, so that lubrication is further disadvantageous.

  The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a drive device for a hybrid vehicle in which a lubricating oil supply amount to a bearing that rotatably supports a counter gear mechanism is ensured. It is to provide a control device.

  The subject matter of the first invention is (a) an engine, a first electric motor, a first rotating element connected to the engine, a second rotating element connected to the first electric motor, and a second rotating gear connected to the output gear. A power distribution mechanism including three rotating elements; a counter gear mechanism that meshes with a second electric motor, an output gear, and a differential ring gear of a differential gear device; and an oil pump that is rotationally driven by the engine and discharges lubricating oil. A control device for a hybrid vehicle drive device, wherein (b) when the accelerator is off running at a low oil temperature, the engine speed is set to be higher than that when the accelerator is off at a high oil temperature, The engine speed control for canceling at least a part of the increase in the engine friction torque is performed by the first electric motor or the second electric motor.

  The gist of the second invention is that, in the first invention, (c) an engine generated in the engine from the first electric motor during a transient period in which the engine speed is set to a high speed in the engine speed control. The object is to output a canceling transient torque for canceling at least a part of the increase in the friction torque.

  The gist of the third invention is that, in the first invention or the second invention, (d) in the engine speed control, the engine speed is set to the high speed after a transient period in which the engine speed is set to a high speed. The steady period control to maintain the number is generated by outputting a pulling torque for raising the engine speed to the high speed from the first electric motor, and raising the engine speed to the high speed. The canceling steady torque for canceling at least part of the friction torque of the engine is output from the second electric motor.

  The gist of the fourth invention is that, in the first invention, the second invention, or the third invention, (e) the engine speed control is performed at a high vehicle speed equal to or higher than a predetermined vehicle speed.

  According to the first invention, the bearing that rotatably supports the counter gear mechanism is disadvantageous in lubrication particularly when the accelerator is driven off at a low oil temperature. At this time, the engine speed is high at the high oil temperature. Since the pump discharge amount is increased by setting the number of revolutions to be higher than when the accelerator is off, lubrication failure is suppressed. Further, at least a part of the increase in the engine friction torque due to the high engine speed is offset by the first electric motor or the second electric motor, so that the driven torque increases and the bearing is supplied to the bearing. An increase in the thrust load is reduced.

  In the transient period control in which the engine speed is decreased at a predetermined rate of change by the engine speed control, it is better to perform the control by the first electric motor. For this reason, according to the second aspect of the invention, the canceling transient torque for canceling at least a part of the increase in the engine friction torque generated in the engine is output from the first electric motor. Sex is obtained.

  According to the third aspect of the present invention, the steady period control for maintaining the engine speed at the high speed after a transient period in which the engine speed is decreased at a predetermined change rate in the engine speed control is performed by the first motor. An amount of torque that increases the engine rotational speed to the high rotational speed and outputs at least a part of the engine friction torque generated by increasing the engine rotational speed to the high rotational speed. A canceling steady torque is output from the second electric motor. Therefore, in the steady period control of the engine speed control, the engine speed is maintained at the high speed by outputting the pulling torque from the first motor, and the canceling steady torque is applied from the second motor. By outputting, at least a part of the engine friction torque generated by raising the engine speed to the high speed is steadily offset. As a result, when the accelerator is driven off at a low oil temperature, the pump speed is increased by setting the engine speed to a higher speed than when the accelerator is off at a high oil temperature. Lubrication failure of the bearing that rotatably supports the gear mechanism is suppressed.

  The poor lubrication of the bearing that rotatably supports the counter gear mechanism when the accelerator is off at the low oil temperature is particularly problematic at high vehicle speeds. For this reason, according to the fourth aspect of the present invention, the engine speed control can be performed at a high vehicle speed that is equal to or higher than a predetermined vehicle speed, and the frequency of cancel torque control of the first motor or the second motor can be reduced. .

It is a figure explaining the structure of the drive device of a hybrid vehicle of one Example of this invention, and an electronic controller. It is principal part sectional drawing of the transaxle explaining the structure of the drive device of the hybrid vehicle of FIG. FIG. 4 is a diagram for explaining a four-axis configuration of the transaxle in FIG. 2 and a supply path of the scraped oil to the bearing of the counter shaft by the diff ring gear. It is a figure explaining the supply path | route with respect to the bearing of the countershaft of scooping up oil with a diff ring gear in case a transaxle is a 3 axis | shaft structure. It is a functional block diagram explaining the principal part of the control function of the electronic control apparatus of FIG. 6 is a time chart for explaining a main part of the control operation of the engine speed control obtained by the control function shown in FIG. 5 in the drive device shown in FIGS. FIG. 7 is a time chart corresponding to FIG. 6 for explaining the operation in the engine speed stop control when the accelerator is off in the drive device shown in FIG. 4. It is a time chart explaining the principal part of the control action of the electronic controller of FIG.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the drawings used for the following description, the dimensional ratio of each part is not necessarily drawn accurately.

  FIG. 1 is a diagram illustrating the configuration of a drive device 12 and a control device of a hybrid vehicle (hereinafter referred to as a vehicle) 10 to which the present invention is applied.

  In FIG. 1, the drive device 12 includes an engine 14 as a driving force source for traveling, and a transaxle 16 that is a power transmission device that transmits the power of the engine 14 to drive wheels (not shown). The transaxle 16 is a planetary gear type that distributes the power output from the engine 14 to the first electric motor MG1 and the annular output gear shaft 22 via a damper 18 and an input shaft 20 that can rotate about the axis C1. Power distribution mechanism 24, counter driven gear 26a meshing with counter drive gear (output gear) 22a of output gear shaft 22, and differential drive gear 26b meshing with diff ring gear, and the shaft end is rotated by a pair of thrust bearings B1 and B2. The counter gear mechanism 26 is composed of a countershaft 26s that can be supported and is rotatable about an axis C2 parallel to the axis C1, and an output gear 27 that meshes with the counter driven gear 26a of the counter shaft 26, and is parallel to the axis C1. Second electric motor MG2 rotatable around a long axis C3 and a counter shaft Has 6 differential drive gear 26b and non-rotatably mates differential ring gear 28a of a rotatable differential unit 28 is provided around the C4 axis parallel to the axis C1. The power distribution mechanism 24 includes three rotating elements, that is, a sun gear S that can rotate around the axis C1 of the input shaft 20, a ring gear R that is disposed on the outer peripheral side of the sun gear S, the sun gear S and the ring gear R, And a carrier CA that supports the meshing pinion gear P so as to rotate and revolve. The sun gear S corresponding to the second rotating element is connected to the end portion on the engine 14 side of the substantially cylindrical rotating shaft 32 of the first electric motor MG1 by non-relative rotation by spline fitting (see FIG. 2). The carrier CA corresponding to the first rotating element is connected to a flange 20a (see FIG. 2) extending in the radial direction from the input shaft 20 so as not to be relatively rotatable. The ring gear R corresponding to the third rotating element is formed integrally with the inner peripheral portion of the output gear shaft 22 where the counter drive gear 22a is formed.

  In the transaxle 16 having four shafts as described above, the power of the engine 14 input via the damper 18 and the input shaft 20 is transmitted to the cylindrical output gear shaft 22, and the counter shaft is output from the output gear shaft 22. 26, the differential device 28, a pair of drive shafts 30 and the like are sequentially transmitted to the drive wheels, while the power of the second electric motor MG2 is sequentially transmitted through the counter shaft 26, the differential device 28, the pair of drive shafts 30 and the like. It is transmitted to the drive wheel.

  A container-shaped transaxle case 34 of the transaxle 16 partially shown in FIG. 2 includes a first case 34a, a cylindrical second case 34b, and an axially engine 14 side of the cylindrical second case 34b. Is a non-rotating member composed of three case members of a third case 34c that functions as a side wall by closing the opposite side opening, and the axial end surfaces (matching surfaces) of the case members are fastened by bolts. Thus, it is configured as one transaxle case 34.

  As shown in FIGS. 1 and 2, one end of the input shaft 20 is connected to the crankshaft 14 a of the engine 14 via the damper 18, and is rotated by the engine 14. A cylindrical oil pump drive shaft 36 is connected to the other end of the input shaft 20 so as not to be relatively rotatable by, for example, spline fitting, and the oil pump drive shaft is driven by the input shaft 20 being rotated by the engine 14. The oil pump 38 is driven through 36, and the oil that has recirculated is sucked and discharged from the oil pump 38. The oil functions as hydraulic oil and lubricating oil. As shown in FIG. 2, the oil pump 38 is an internal gear type in which an annular driven gear 38a and a drive gear 38b having outer peripheral teeth meshing with inner peripheral teeth of the driven gear 38a are engaged with each other. An end of 36 on the oil pump 38 side is connected to the drive gear 38b so as not to be relatively rotatable.

  As shown in FIG. 2, the oil pump 38 has a pump body 40 fixed to the third case 34c, and a flat plate 42 interposed between the pump body 40 and the third case 34c. And a pump chamber 44 formed between the plate 42 and the pump body 40, and a driven gear 38a and a drive gear 38b are rotatably accommodated in the pump chamber 44. The pump body 40 is integrally fixed to the third case 34 c and is a case member that functions as a part of the transaxle case 34.

  As shown in FIG. 2, a bearing 46 is interposed between the pump body 40 and the end of the rotating shaft 32 on the oil pump 38 side, and the flange 34 d of the second case 34 b and the rotating shaft 32 on the engine 14 side are interposed. A bearing 48 is interposed between the end portions. The cylindrical rotary shaft 32 is fixed to the transaxle case 34 by a pair of bearings 46 and 48 so as to be rotatable around the axis C2.

  The first electric motor MG1 includes a cylindrical stator 52 fixed in a second case 34b by a bolt 50 in a container-shaped transaxle case 34, and a predetermined gap (air gap) inside the stator 52. A rotor 54 fixed to the rotary shaft 32 and a cylindrical rotary shaft 32 that rotatably supports the rotor 54 about the axis C2 are provided, and penetrated in a substantially columnar shape along the axis C2 of the rotary shaft 32. The oil supplied from the oil pump 38 to the longitudinal through hole 32a is caused to flow out to the outer peripheral side through a plurality of cooling oil holes 32c provided through the peripheral wall 32b of the rotating shaft 32, and the rotor 54 of the first electric motor MG1 and the like. It is to be cooled.

  A tubular oil pump drive shaft 36 that passes through the longitudinal passage hole 32a in the direction of the axis C2 is disposed in the longitudinal passage hole 32a of the rotary shaft 32. The oil pump drive shaft 36 includes an axial line. A plurality (two in FIG. 2) provided through the peripheral wall 36b of the oil pump drive shaft 36 so that the through hole 36a penetrating in the C2 direction and the through hole 36a communicate with the longitudinal through hole 32a of the rotary shaft 32. ) Supply holes 36c. Further, when the oil pump 38 is rotationally driven by the engine 14 via the oil pump drive shaft 36, the oil is discharged into the through hole 36a of the oil pump drive shaft 36, and the discharged oil is driven by the oil pump. A portion of the oil that has flowed out from the supply hole 36c of the shaft 36 to the outer peripheral side and is supplied into the longitudinal through hole 32a of the rotating shaft 32 and has reached the inner peripheral side of the cylindrical output gear shaft 22 The counter gear mechanism 26 is supplied through a counter gear cooling oil hole 39 formed through the output gear shaft 22 in the radial direction. An arrow F <b> 1 shown in FIG. 2 indicates the flow path of the input system oil supplied to the counter gear mechanism 26 through the longitudinal through hole 32 a of the rotating shaft 32.

  The rotor 54 of the first electric motor MG1 is adjacent to the rotor core 54a composed of a plurality of disc-shaped electromagnetic steel plates laminated in the direction of the axis C2 on the inner peripheral side of the stator 52, and both ends of the rotor core 54a in the axial direction. And a pair of substantially disc-shaped end plates 56 and 58 fixed to the rotary shaft 32 with the rotor core 54a sandwiched therebetween. Further, the rotor core 54a is formed with a cooling hole 54b penetrating in the direction parallel to the axis C2 in the outer peripheral portion of the rotor core 54a and an inner diameter side of the cooling hole 54b, and on the shaft end surface 54c of the rotor core 54a on the engine 14 side. L-shaped oil supply holes 54f each having an inner opening 54d that opens and an outer peripheral opening 54e that opens in the cooling hole 54b are formed at a plurality of locations. The end plate 56 on the cooling oil hole 32c side of the pair of end plates 56, 58 functions as an oil guide that guides the oil flowing out from the cooling oil hole 32c to the inner opening 54d of the oil supply hole 54f. A plurality of permanent magnets 60 for forming a plurality of magnetic poles on the outer peripheral surface of the rotor core 54a are embedded in the outer peripheral portion of the rotor core 54a.

  The stator 52 of the first electric motor MG1 protrudes in the direction of the axis C2 from both ends of the stator core 52a. Coil ends 52b and 52c are provided. The first electric motor MG1 attracts (or repels) the permanent magnet 60 embedded in the rotor 54 by a moving (rotating) magnetic field created by flowing alternating current through the coil ends 52b and 52c of the stator 52, and causes the rotor 54 to move. It is a synchronous motor used for the hybrid vehicle to rotate.

  The rotary shaft 32 has a peripheral wall 32b of the rotary shaft 32 in parallel with the cooling oil hole 32c so that oil that does not flow out of the oil cooling oil hole 32c in the vertical through hole 32a is discharged directly into the transaxle case 34. A discharge hole 32f provided therethrough is provided. The discharge hole 32f is provided on the inner peripheral side of the coil end 52b so as to discharge oil to the coil end 52b of the stator 52 in the direction of the axis C2.

  A discharge path 68 formed between the pump body 40 and the rotor 54 is provided in the transaxle case 34 in which the first electric motor MG1 is housed, and the discharge hole 32f is a distance from the discharge path 68. Are arranged at relatively short positions.

  The oil pump drive shaft 36 is provided with a lubricating oil hole 36d provided through the peripheral wall 36b at the end of the oil pump drive shaft 36 on the oil pump 38 side. A part of the oil discharged into the pump drive shaft 36 is caused to flow into the lubricating oil hole 36d to lubricate the bearing 46. A lubricating oil passage 62 is formed between the end of the rotating shaft 32 on the oil pump 38 side and the pump body 40 to supply oil flowing out from the lubricating oil hole 36d to the bearing 46. Further, a lubricating oil passage 62 for lubricating the bearing 46 by flowing oil discharged from the oil pump 38 into the oil pump drive shaft 36 into the lubricating oil hole 36d is provided.

  The other part of the oil pumped from the oil pump 38, that is, the MG oil is supplied to the first electric motor MG1 and the second electric motor MG2 along the arrow F2 in FIG.

  FIG. 3 is a diagram showing the relative positional relationship between the axes C1, C2, C3, and C4 of the transaxle 16 of this embodiment configured with four axes. In FIG. 3, the axis C4 of the differential device 28 is set to the lowest position, the axis C3 of the second electric motor MG2 is set to the highest position above the fourth axis C4 in the vertical direction, and the first electric motor MG1 has the first position. The axis C1 is set to an intermediate height position between the third axis C3 and the fourth axis C4 on the side of the line connecting the third axis C3 and the fourth axis C4, and the second axis C2 of the counter shaft 26 is set. Is set at a position surrounded by the first axis C1, the third axis C3, and the fourth axis C4.

  In the transaxle 16 in which the relative positions of the respective axes C1, C2, C3, and C4 are set as described above, the thrust bearings B1 and B2 that rotatably support the countershaft 26s are provided on the differential gear unit 28. Although it is lubricated by the oil scraped up by the ring gear 28a, it is not always sufficient. It is difficult to directly supply the oil scraped up by the diff ring gear 28a to the counter shaft 26 on the third axis C3 sandwiched between the first axis C1 and the second axis C2, and the oil is picked up by the diff ring gear 28a. The oil is supplied from the differential ring gear 28a to the output gear (counter drive gear) 22a, and the oil is scraped up by the counter driven gear 26a and supplied to the thrust bearings B1 and B2 that rotatably support the counter shaft 26s. Therefore, stable lubrication is difficult, and particularly in a low oil temperature state where the oil viscosity is high, there is a problem that the amount of oil supply cannot be obtained further. In particular, of the pair of thrust bearings B1 and B2 that rotatably support the counter shaft 26, the thrust bearing B2 that supports the shaft end on the side away from the differential drive gear 26b is a differential shaft that is the oil scooping site. It is separated from the drive gear 26a, which is disadvantageous for the lubricating oil. Further, when the vehicle is driven, a load in the thrust direction due to the torsion angle of the counter driven gear 26a, which is an inclined tooth, is applied to the bearing B2, so that the lubrication is further disadvantageous.

  FIG. 4 is a diagram for explaining lubrication by the scraping oil in the power transmission device of the hybrid vehicle having a three-axis structure in which the axis C1 of the first electric motor M1 and the axis C3 of the second electric motor MG are coaxial. In FIG. 4, the oil scooped up by the diff ring gear 28a is directly supplied to the counter driven gear, and the oil is supplied to the bearing of the counter shaft. This is more advantageous than the four-shaft hybrid vehicle drive device shown in FIG.

  Returning to FIG. 1, the hybrid vehicle 10 is provided with an electronic control unit 80 that controls the engine 14, for example. The electronic control unit 80 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like, and the CPU uses a temporary storage function of the RAM according to a program stored in the ROM in advance. Various controls of the hybrid vehicle 10 are executed by performing signal processing. For example, the electronic control unit 80 is configured to execute vehicle control such as hybrid drive control related to the engine 12, the first electric motor MG1, the second electric motor MG2, and the like. It is configured separately for output control of MG1 and MG2. The electronic control unit 80 includes various sensors (for example, rotation speed sensors 66, 67, 69, an accelerator opening sensor 70, a throttle valve opening sensor 72, an oil temperature sensor 74, a battery sensor provided in the hybrid vehicle 10. 76, for example, an engine speed Ne (rpm) representing the engine speed of the engine 12, and an output speed Nout (rpm representing the speed of the output gear 14 corresponding to the vehicle speed V (km / h). ), MG1 rotational speed Nmg1 (rpm) representing the rotational speed of the first electric motor MG1, MG2 rotational speed Nmg2 (rpm) representing the rotational speed of the second electric motor MG2, and driving with respect to the driving force of the vehicle 10 (the same driving torque etc.) Accelerator opening degree Acc representing the required amount of the engineer is provided in the intake pipe 54 of the engine 12 and is opened and closed by a throttle actuator. The throttle valve opening θth (%) representing the opening angle of the electronic throttle valve, the oil temperature Toil (° C.), the battery temperature THbat of the power storage device 77, the battery charge / discharge current Ibat, the battery voltage Vbat, etc.) are respectively input. The Further, the electronic control device 80 sends various output command signals (for example, engine control command signals and motor control command signals (shift control command) to the devices such as the engine 12 (for example, fuel injection device, ignition device, throttle actuator), inverter 78, and the like. Signal) or the like is output. The electronic control unit 80 sequentially calculates the state of charge (charge capacity) SOC of the power storage device 77 based on, for example, the battery temperature, the battery charge / discharge current, the battery voltage, and the like.

  FIG. 5 is a functional block diagram for explaining the main part of the control function by the electronic control unit 80. In FIG. 5, the hybrid control means, that is, the hybrid control unit 82 operates the engine 12 in an efficient operating range, for example, while distributing the driving force between the engine 12 and the second electric motor MG2 and the power generation of the first electric motor MG1. A speed ratio γ as an electric continuously variable transmission that changes the reaction force to be optimized is controlled. Specifically, the hybrid control unit 82 calculates the target output (user required power) of the vehicle 10 from the accelerator opening Acc and the vehicle speed V at the traveling vehicle speed V at that time, and the target output and the required charging value (charging) The required total target output is calculated from the required power), and the target engine output (required engine output, output torque, auxiliary load, assist torque of the second electric motor MG2 and the like is taken into account so that the total target output is obtained. Engine required power) Petgt is calculated, and the actual engine 12 is obtained so that the target (requested) engine speed Ne * and the target output torque (requested output torque) Te * of the engine 12 can be obtained. Controls the rotational speed Ne and the output torque Te, and controls the output or power generation of the first electric motor MG1 and the second electric motor MG2. . For example, the hybrid control unit 82 stops the operation of the engine 12 when the accelerator is off and makes the vehicle coast. At this time, if necessary, an appropriate braking force is generated by regeneration of the second electric motor MG2, and the same action as a so-called engine brake is generated.

  Further, the hybrid control unit 82 uses the electric CVT function (differential action) of the power distribution mechanism 24 regardless of whether the vehicle 10 is stopped or traveling, that is, regardless of the output rotational speed Nout restricted by the vehicle speed V. By controlling the MG1 rotational speed Nmg1, the engine rotational speed Ne can be maintained substantially constant, or the rotational speed can be controlled to an arbitrary rotational speed (for example, the engine rotational speed Ne to be changed). For example, when the engine speed Ne is increased while the vehicle is traveling, the hybrid control unit 82 increases the MG1 speed Nmg1 while maintaining the output speed Nout substantially constant.

  Further, the hybrid control unit 82 drives the second electric motor MG2 with the electric power from the power storage device 77 in a state where the operation of the engine 12 is stopped, and travels using only the second electric motor MG2 as a driving force source (EV traveling). ) Can be performed. The EV traveling is performed in an EV possible region where the target output is smaller than a predetermined threshold value (that is, a relatively low torque range of the required driving torque and a relatively low vehicle speed range of the vehicle speed V), and charging of the power storage device 77 is performed. The capacity SOC is in an EV-capable region (that is, a relatively high charge capacity region of the charge capacity SOC) larger than a predetermined threshold SOC1 as a charge capacity that is small enough to charge the power storage device 77 with the power of the engine 12. If executed. The required driving torque (the required driving force is also agreed) is calculated from the accelerator opening Acc and the vehicle speed V, for example, similarly to the target output.

  The engine speed control unit 84 is a request in which the vehicle speed V is equal to or higher than a preset vehicle speed determination value V1, and the accelerator pedal is released (for example, 0%), that is, the required output torque Te * is preset. Below the output torque determination value Te1 *, the oil temperature Toil is below the preset low oil temperature determination value Toil1, and the engine speed Ne or its target value Ne * is set in advance. When the value is less than the value Ne1, in order to discharge the oil from the oil pump 38 and particularly improve the lubricity of the counter gear mechanism 26, for example, the engine speed Ne when the explosion operation is stopped is reduced to a low oil whose oil temperature Toil is set in advance. Compared to the case where the accelerator is off at the temperature determination value Toil1 or higher, the value is raised by a predetermined value ΔNeup and maintained. Using the first electric motor MG1 and / or the second electric motor MG2, thereby offsetting the engine friction torque (rotation resistance torque) based on the raising of the engine speed Ne. In the present embodiment, this control is referred to as engine speed control. The predetermined value ΔNeup is a necessary and sufficient value for obtaining sufficient lubrication of the bearing B2 of the countershaft 26s particularly at a low oil temperature, and is determined experimentally in advance. The required output torque determination value Te1 * is experimentally determined in order to determine whether the required output torque Te * is substantially zero, that is, the accelerator off state. The low oil temperature determination value Toil1 is a temperature at which the lubrication of the bearing B2 of the counter shaft 26s is particularly insufficient due to the high viscosity of the oil, and is experimentally determined in advance, for example, at about -20 to -30 ° C. The vehicle speed determination value V1 is a vehicle speed that does not require the engine speed control, and is experimentally determined in advance, for example, at about 150 km / h. The engine speed determination value Ne1 is used to determine whether the engine speed Ne when the explosion operation is stopped is in a range suitable for engine speed control, and is experimentally obtained in advance, for example, at about 2000 to 2500 rpm.

  The engine speed control unit 84 includes an engine speed control condition establishment determination unit 86, an engine speed transient period determination unit 88, a transient period control unit 90, a steady period control unit 92, and an engine speed control end determination unit 94. I have.

  For example, the engine speed control condition establishment determining unit 86 determines that the vehicle speed V is equal to or higher than a predetermined vehicle speed determination value V1, an accelerator off state (for example, 0%) in which the accelerator pedal is returned, that is, a required output torque Te *. Falls below the preset required output torque judgment value Te1 *, the engine speed Ne or its target value Ne * falls below the preset engine speed judgment value Ne1, and the oil temperature Toil is preset. The engine speed control condition is determined not to be satisfied if any of the lower oil temperature determination value Toil1 is negative, but if all are positive, the engine speed control condition is satisfied. judge.

  The engine speed transition period determination unit 88 is a transition period Tt in which the engine speed Ne decreases when the engine speed control unit 84 starts executing the engine speed control, or the engine speed Ne is constant. For example, the rotation difference ΔNe (= Ne−Ne *) between the engine rotation speed Ne and the target engine rotation speed Ne * is equal to or greater than a predetermined rotation difference determination value ΔNe1. Or based on whether or not the actual change rate dNe / dt of the engine speed Ne is greater than or equal to a preset change rate determination value dNe1 / dt.

  When the engine speed transition period determining unit 86 determines that the engine speed transition period is the transition period Tt of the engine speed control, the transient period control unit 90 has an oil temperature Toil equal to or higher than a preset low oil temperature determination value Toil1. In the transition period Tt in which the engine speed Ne is set to the predetermined value ΔNeup so that the engine speed Ne becomes the high speed in the engine speed control, in order to obtain high control characteristics, A canceling transient torque for canceling an increase in engine friction torque generated in the engine 14 from the first electric motor MG1 due to the rotational speed is output.

  When the engine speed transition period determining unit 86 determines that the steady period control unit 92 is in the steady period Ts of the engine speed control, the oil temperature Toil is equal to or higher than a preset low oil temperature determination value Toil1. In the steady period Ts in which the engine speed Ne is maintained at a high speed obtained by raising the engine speed Ne by a predetermined value ΔNeup compared to the case where the accelerator is off, the engine speed Ne is increased from the first electric motor MG1 by the predetermined value ΔNeup. The second electric motor MG2 outputs a canceling steady torque for canceling the friction torque of the engine 14 generated by outputting the pulling torque and raising the engine rotational speed Ne to a high rotational speed that is increased by a predetermined value ΔNeup.

  For example, the engine speed control end determination unit 94 determines that the vehicle speed V is below a preset vehicle speed determination value V1, that the accelerator pedal is not in an accelerator off state (for example, 0%), the engine speed Ne or If either of the target value is equal to or higher than the preset engine speed determination value Ne1 and the oil temperature Toil is equal to or higher than the preset low oil temperature determination value Toil1, the engine It is determined whether the end condition for the rotational speed control is satisfied.

  FIG. 6 is a flowchart for explaining a main part of the control operation of the electronic control unit 80, and is repeatedly executed. The control operation will be described below with reference to the flowchart of FIG. 6 and the time chart of FIG.

  In FIG. 6, in steps S1 to S4 (hereinafter, steps are omitted) corresponding to the engine speed control condition establishment determination unit 86, it is determined whether or not the engine speed control condition is satisfied. That is, in S1, it is determined whether or not the oil temperature Toil falls below a preset low oil temperature determination value (threshold value) Toil1, and in S2, the vehicle speed V is equal to or higher than a preset vehicle speed determination value (threshold value) V1. In S3, it is determined whether the engine speed Ne or its target value Ne * falls below a preset engine speed determination value (threshold value) Ne1, and in S4, the vehicle In order to determine the driven (power-off) state of the vehicle, the accelerator-off state (for example, 0%) in which the accelerator pedal is returned, that is, the required output torque Te * is a preset required output torque determination value (threshold) Te1 *. It is determined whether or not the value is below. If any one of the determinations of S1 to S4 is negative, the engine speed control condition is not satisfied, and this routine is terminated. However, if all of the determinations in S1 to S4 are affirmed, it is determined that the engine speed control condition is satisfied. Next, in S5 corresponding to the engine speed transition period determining unit 88, a speed difference determination in which a rotational difference ΔNe (= Ne−Ne *) between the actual engine speed Ne and the target engine speed Ne * is set in advance. It is determined whether or not the value (threshold value) ΔNe1 or more.

  Initially, the determination in S5 is affirmed, so in S6 corresponding to the transient period control unit 90, the transient period control for reducing the engine speed Ne in the engine speed control is started. From time t1 to time t2 in FIG. 7 indicates a period during which the transition period control is executed. In the transient period control, for example, the engine speed Ne is decreased to a predetermined value Neh at a predetermined change rate by changing the rotation speed Nmg1 of the first electric motor MG1 that has been rotating forward until then to negative rotation. In the transition period control, as shown in FIG. 7A, the torque Tmg1 of the first electric motor MG1 is increased from a negative value so far toward zero at a predetermined change rate. As a result, the friction torque of the engine 14 due to the rotation of the engine 14 in the operation stop state is canceled, and the drop of the output shaft torque Tout of the output gear shaft 22 is eliminated as shown in FIG.

  Next, in S7 and S8 corresponding to the engine speed control end determination unit 94, whether the oil temperature Toil is equal to or higher than a preset low oil temperature determination value Toil1, and the vehicle speed V is a predetermined vehicle speed determination value V1. It is determined whether or not it falls below. When the determinations at S7 and S8 are both negative, S5 and subsequent steps are repeatedly executed. However, if the determination in any of S7 and S8 is affirmed, normal control is returned in S9. The normal control is a state before starting the engine speed control, that is, coasting control in which the engine 12 is stopped by the hybrid control unit 82 when the accelerator is off.

  When the determination of S5 corresponding to the engine speed transition period determination unit 88 is negative while S5 and subsequent steps are repeatedly executed, that is, in the engine speed control, the engine speed Ne reduced to the predetermined value Neh is maintained. If it is determined that it is a steady period, the steady period control is performed in S10 corresponding to the steady period control unit 92. From time t2 to time t3 in FIG. 7 indicates a period in which the steady period control is executed. In this steady period control, as shown in FIG. 7 (b), the output torque Tmg1 of the first electric motor MG1 is made larger than that in the case where the steady period control is not performed, so that the engine speed Ne is predetermined from zero. The predetermined value Neh is maintained by being raised to the value Neh. Further, in this steady period control, as shown in FIG. 7C, the output torque Tmg2 of the second electric motor MG2 is made larger than that in the case where the steady period control is not performed, so that the engine 14 is in a stopped state. The friction torque of the engine 14 accompanying the rotation in which the engine speed Ne is increased from a zero value to a predetermined value Neh is cancelled. As a result, the shock that the output shaft torque Tout of the output gear shaft 22 suddenly decreases is avoided.

  Next, in S11 and S12 corresponding to the engine speed control end determination unit 94, whether the oil temperature Toil is equal to or higher than a preset low oil temperature determination value Toil1 and the vehicle speed V is a preset vehicle speed determination value V1. It is determined whether or not it falls below. If the determinations at S11 and S12 are both negative, S10 and subsequent steps are repeatedly executed. However, if the determination in any of S11 and S12 is affirmed, normal control is returned in S9. This state is shown at time t4 in FIG.

  Incidentally, FIG. 8 is a time chart for explaining the operation in the normal control. In FIG. 8, when the accelerator is off, the operation of the engine 12 is stopped by the hybrid control unit 82 at time t1, and the coasting running of the vehicle is started. In the normal period of this normal control, the output speed Tmg1 is slightly output from the first electric motor MG1 in order to maintain the engine speed Ne at zero rotation, and in order to generate an appropriate braking force, that is, the output gear shaft 22 In order to make the output shaft torque Tout slightly negative, the regeneration of the second electric motor MG2 is performed, and the same action as a so-called engine brake is generated.

  Between the time t1 and time t2 of FIG. 8, the transition period which transfers to the normal control at the time of the said accelerator off is shown. During this transition period, the output torque Te of the engine 14 due to the engine 14 being inoperative is suddenly reduced, and the rotational speed Nmg1 of the first electric motor MG is reduced at a predetermined rate of change, thereby rotating the engine. The number Ne is reduced toward zero rotation at a predetermined rate of change. In this transition period, the output torque Tmg1 of the first electric motor MG1 is maintained at zero, and the regeneration of the second electric motor MG2 is performed in the same manner as in the steady period, and the engine friction torque in the transition period is canceled. Therefore, as shown in FIG. 8E, the output shaft torque Tout of the output gear shaft 22 in response to the sudden decrease in the output torque Te of the engine 14 that is generated when the engine 14 is not operated. However, it was inevitable that there would be a shock that suddenly decreased.

  As described above, the bearings B1 and B2 that support the counter gear mechanism 26 so that the counter shaft 26s can rotate are electronically controlled according to this embodiment in a situation where lubrication is particularly disadvantageous when the accelerator is driven off at a low oil temperature. According to the device 80, the engine speed Ne is set to a predetermined value Neh (high engine speed) that is higher than the zero value compared to when the accelerator is off at a high oil temperature. Since the discharge amount is increased, poor lubrication of the bearings B1 and B2 is suppressed. Further, the increase in engine friction torque due to the high rotational speed Ne of the engine 14 is offset by the first electric motor MG1 or the second electric motor MG2, so that the driven torque increases and the bearing B1 and An increase in the thrust load on B2 is reduced.

  Further, when the engine speed Ne is decreased at a predetermined rate of change by the engine speed control, the control is better performed by the first electric motor MG1. According to the electronic control unit 80 of the present embodiment, since the canceling transient torque for canceling the increase in the engine friction torque generated in the engine 14 is output from the first electric motor MG1, high controllability can be achieved with respect to the transient period control. can get.

  According to the electronic control unit 80 of the present embodiment, the engine speed Ne is set to a high speed higher than a zero value, that is, a predetermined value Neh after a transient period in which the engine speed Ne is decreased at a predetermined change rate in the engine speed control. The steady period control that is maintained at the non-operation generated by the first motor MG1 outputting a pulling torque for raising the engine speed Ne to the high speed and raising the engine speed Ne to the high speed. The canceling steady torque for canceling the friction torque of the engine 14 is output from the second electric motor MG2. For this reason, in the steady period control of the engine speed control, the engine torque Ne is maintained at the high speed by outputting the pulling torque from the first electric motor MG1, and the canceling steady torque is applied from the second electric motor MG2. By outputting, the friction torque of the non-operating engine 14 generated by raising the engine speed Ne to the high speed is steadily offset. As a result, when the accelerator is turned off (driven) at a low oil temperature, the engine speed Ne is set to be higher than that when the accelerator is off at a high oil temperature. Therefore, poor lubrication of the bearing 26s that rotatably supports the counter gear mechanism 26 is suppressed.

  The poor lubrication of the bearings B1 and B2 that rotatably support the counter gear mechanism 26 when the accelerator is off at the low oil temperature is a problem particularly at high vehicle speeds. For this reason, according to the electronic control unit 80 of the present embodiment, the engine speed control can be performed at a high vehicle speed equal to or higher than the predetermined vehicle speed V1, and the frequency of cancel torque control of the first electric motor MG1 or the second electric motor MG2 can be reduced. As a result, fuel consumption can be 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, the increase in the engine friction torque due to the high speed Ne of the engine 14 is offset by the first electric motor MG1 or the second electric motor MG2, but the increase Some may be offset. Even in such a case, the effect that the driven torque is increased and the thrust load on the bearings B1 and B2 is increased is reduced. That is, it is sufficient that at least a part of the increase is offset.

  The above description is merely an example of the present invention, and the present invention can be applied to other modes in which various modifications and improvements are made without departing from the spirit of the present invention.

10: Hybrid vehicle 12: Drive device 14: Engine 22: Output gear shaft 22a: Counter drive gear (output gear)
24: Power distribution mechanism 26: Counter gear mechanism 26a: Counter driven gear 28: Differential device (differential gear device)
28a: diff ring gear 38: oil pump MG1: first electric motor MG2: second electric motor

Claims (4)

A power distribution mechanism including an engine, a first electric motor, a first rotating element connected to the engine, a second rotating element connected to the first electric motor, and a third rotating element connected to an output gear; A control device for a hybrid vehicle drive device having a second motor, a counter gear mechanism that meshes with the output gear, and a differential ring gear of a differential gear device, and an oil pump that is rotationally driven by the engine and discharges lubricating oil. There,
When the accelerator is turned off at a low oil temperature, the engine speed is set to a higher value than when the accelerator is turned off at a high oil temperature, and the increased amount of the engine friction torque is increased by the first motor or the second motor. A control device for a hybrid vehicle drive device, wherein engine speed control is performed to cancel at least a part thereof.   In the engine speed control, during the transition period in which the engine speed is set to a high speed, a canceling transient torque for canceling at least a part of the increase in engine friction torque generated in the engine from the first electric motor is output. The control device for a hybrid vehicle drive device according to claim 1, wherein:   In the engine speed control, the steady period control for maintaining the engine speed at the high speed after a transition period in which the engine speed is set to the high speed is obtained by changing the engine speed from the first motor to the high speed. The second electric motor has a canceling steady torque for canceling at least a part of the engine friction torque generated by increasing the engine rotational speed to the high rotational speed. 3. The control device for a hybrid vehicle drive device according to claim 1, wherein the control device outputs the hybrid vehicle drive device.   4. The control device for a hybrid vehicle drive device according to claim 1, wherein the engine speed control is performed at a high vehicle speed equal to or higher than a predetermined vehicle speed. 5.

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