JP6790750B2 - Control device for vehicle power transmission device - Google Patents

Description

The present invention applies a narrow belt pressure that suppresses belt slippage of a belt-type continuously variable transmission during clutch-to-clutch shift (CtoC shift) in a vehicle equipped with a belt-type continuously variable transmission mechanism and a gear-type transmission mechanism in parallel. Regarding hydraulic technology to obtain.

From the driving force source via a belt-type stepless speed change mechanism provided in parallel between an input rotating member through which power from the driving force source is transmitted and an output rotating member that outputs the power to the driving wheels. A second power that transmits the power of the driving force source to the driving wheel side via a first power transmission path that transmits the power to the driving wheel side and a gear type transmission mechanism in which one or a plurality of gear stages are formed. A transmission path, a first power transmission path, and a clutch mechanism for selectively switching the second power transmission path are provided, and the clutch mechanism is engaged when the first power transmission path is selected. At the same time, it is engaged with the output side member of the belt type stepless transmission mechanism or the first clutch arranged on the downstream side in the torque transmission path from the output side member when the second power transmission path is selected. Vehicle power transmission devices, including a second clutch, are known. For example, the vehicle power transmission device of Patent Document 1 is that.

In the vehicle power transmission device of Patent Document 1, the belt-type continuously variable transmission mechanism is provided on a primary pulley having a variable effective diameter provided on the input rotating member and a rotating shaft coaxial with the output rotating member. It is provided with a secondary pulley having a variable effective diameter and a transmission belt wound between the primary pulley and the secondary pulley. The first clutch engages and disengages between the rotating shaft provided with the secondary pulley and the output rotating member. The second clutch engages and disengages between an input element to which a driving force is input from the driving force source of the differential gear type forward / backward switching mechanism and an output element indirectly connected to the output rotating member. The first power transmission path and the second power transmission path are selectively switched by a shift (clutch to clutch shift (CtoC shift)) in which the first clutch and the second clutch are gripped.

Japanese Unexamined Patent Publication No. 2015-400143

By the way, the first power transmission path via the belt-type stepless speed change mechanism and the second power transmission path via the gear-type transmission mechanism as in Patent Document 1 are selectively switched by the clutch mechanism. In the power transmission device for vehicles, the belt narrow pressure of the primary pulley and the secondary pulley is set to an appropriate value in order to suppress the belt slip when the first clutch and the second clutch are engaged and disengaged by the CtoC shift. Must be set. Therefore, for example, the belt slip that applies a belt narrow pressure for suppressing the belt slip to the belt type stepless speed change mechanism based on the torque obtained by adding the maximum inner shuttle to the engine torque output from the engine as the driving force source. It is conceivable to set the limit thrust uniformly and control the narrow pressure (thrust) of the primary pulley and the secondary pulley from the belt slip limit thrust. Here, the above-mentioned maximum inertia torque is an inertia torque when the rotation change is maximum when shifting at the maximum shifting speed. However, the belt slip limit thrust set uniformly during CtoC shifting in consideration of the maximum inertia shuttle does not accurately reflect the actual input torque of the belt-type continuously variable transmission mechanism during CtoC shifting, so the primary pulley In addition, there is a problem that the hydraulic pressure for applying a narrow pressure to the secondary pulley becomes excessive and the fuel consumption may decrease.

The present invention has been made in the background of the above circumstances, and an object of the present invention is a CtoC speed change in a vehicle power transmission device provided with a belt type continuously variable transmission mechanism and a gear type transmission mechanism in parallel. The purpose is to suppress the excessive hydraulic pressure that applies a narrow belt pressure to the belt-type continuously variable transmission mechanism and the resulting decrease in fuel consumption.

The gist of the present invention is a belt provided in parallel between an input rotating member in which power from a driving force source is transmitted via a torque converter and an output rotating member that outputs the power to drive wheels. The drive is carried out via a first power transmission path for transmitting power from the drive force source to the drive wheel side via a stepless speed change mechanism, and a gear type transmission mechanism in which one or a plurality of gear stages are formed. The clutch mechanism includes a second power transmission path for transmitting the power of the power source to the drive wheel side and a clutch mechanism for selectively switching between the first power transmission path and the second power transmission path. A first clutch that is engaged when the first power transmission path is selected and is arranged on the output side member of the belt type stepless speed change mechanism or on the downstream side of the output side member in the torque transmission path. When the control device of the vehicle power transmission device including the second clutch that is engaged when the second power transmission path is selected, and the first clutch and the second clutch are re-engaged. When the input torque to the belt-type stepless speed change mechanism is upshifting by gripping the second clutch to the first clutch, the torque capacity of the first clutch is changed to the belt-type stepless speed change. The larger value of the first calculated value divided by the gear ratio of the mechanism and the lower limit guard value obtained by dividing the drag torque of the first clutch by the gear ratio of the belt-type stepless speed change mechanism is set. When the downshift is in progress due to the change from one clutch to the second clutch, the smaller value of the first calculated value and the turbine torque output from the turbine of the torque converter is set, and the above-mentioned The purpose is to control the narrow belt pressure of the belt-type stepless speed change mechanism based on the input torque.

According to the present invention, the input torque to the belt-type stepless speed change mechanism when the first clutch and the second clutch are gripped is upshifted by gripping the second clutch to the first clutch. If it is, the first calculated value obtained by dividing the torque capacity of the first clutch by the gear ratio of the belt-type stepless speed change mechanism and the drag torque of the first clutch are the gear ratio of the belt-type stepless speed change mechanism. When the larger value of the lower limit guard value divided by is set and the downshift is in progress due to the gripping from the first clutch to the second clutch, the first calculated value and the torque converter The smaller value of the clutch torque output from the clutch is set, and the narrow belt pressure of the belt-type stepless speed change mechanism is controlled based on the input torque. Therefore, when the torque capacity of the first clutch is divided by the actual gear ratio of the belt-type continuously variable transmission mechanism, the actual input torque of the belt-type continuously variable transmission mechanism can be obtained, so that the belt changes transiently during CtoC shifting. The necessary and sufficient belt narrow pressure can be set according to the actual input torque of the continuously variable transmission mechanism. As a result, for example, the torque obtained by adding the maximum inner shuttle torque to the engine torque is set as the input torque of the belt-type continuously variable transmission mechanism, and the belt narrow pressure during CtoC shifting is set uniformly. Excessive hydraulic pressure that applies a narrow belt pressure to the speed change mechanism can be suppressed, and a decrease in fuel consumption can be suppressed.

Further, preferably, when the first clutch and the second clutch are re-grasped, the first clutch and the second clutch are re-grasped based on the input torque to the belt-type continuously variable transmission mechanism. The thrust ratio of the belt-type continuously variable transmission mechanism is calculated. Therefore, since the thrust ratio is calculated from the input torque of the belt-type continuously variable transmission mechanism, it reflects the actual input torque, and the thrust ratio is used to the primary pulley of the belt-type continuously variable transmission mechanism. Thrust is calculated. As a result, the delay in starting the upshift of the belt-type continuously variable transmission mechanism after the clutch-to-clutch shift in which the second clutch is released and the first clutch is engaged is suppressed, and the shift performance is improved.

It is a figure explaining the schematic structure of the vehicle to which this invention is applied. It is a figure for demonstrating the switching of the traveling pattern of the power transmission device provided in the vehicle of FIG. It is a figure explaining the main part of the control function and the control system for shift control in the power transmission device of FIG. 1, and is the functional block diagram explaining the main part of the control function of an electronic control device. The control function of the electronic control device of FIG. 3 in the thrust control during CtoC shifting of the continuously variable transmission provided in the power transmission device of FIG. 1 and the control function of a comparative example having a control function different from that of the electronic control device of FIG. It is a figure which shows respectively. It is a flowchart explaining the main part of the control operation of the electronic control device of FIG. An example of the control operation during the upshift by the CtoC shift of the electronic control device of FIG. 3 and the control operation during the upshift of the electronic control device of the comparative example having a control function different from that of the electronic control device of FIG. It is a time chart which shows an example and each.

Hereinafter, an embodiment of the control device for the vehicle power transmission device of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram illustrating a schematic configuration of a vehicle 10 to which the present invention is applied. In FIG. 1, the vehicle 10 includes an engine 12 that functions as a driving force source for traveling, a driving wheel 14, and a power transmission device 16 provided between the engine 12 and the driving wheel 14. The power transmission device 16 is integrally provided in the housing 18 as a non-rotating member with a known torque converter 20 as a fluid transmission device connected to the engine 12 and a turbine shaft which is an output rotating member of the torque converter 20. The input shaft 22 is connected, the belt type stepless transmission 24 as a stepless speed change mechanism connected to the input shaft 22 (hereinafter referred to as the stepless transmission 24), and the forward / backward switching device 26 also connected to the input shaft 22. A common output rotating member of the gear mechanism 28, the stepless transmission 24, and the gear mechanism 28 as a transmission mechanism connected to the input shaft 22 via the forward / reverse switching device 26 and provided in parallel with the stepless transmission 24. A reduction gear device 34 composed of a pair of gears that are provided on a certain output shaft 30, a counter shaft 32, an output shaft 30 and a counter shaft 32 so as to be relatively non-rotatable and mesh with each other, and a gear 36 provided on the counter shaft 32 so as not to be relatively rotatable. It includes a connected differential gear 38, a pair of axles 40 connected to the differential gear 38, and the like. In the power transmission device 16 configured in this way, the power of the engine 12 (torque and force are synonymous unless otherwise specified) is the torque converter 20, the continuously variable transmission 24 (or the forward / backward switching device 26, and the gear mechanism 28). ), The reduction gear device 34, the differential gear 38, the axle 40, and the like are sequentially transmitted to the pair of drive wheels 14.

As described above, the power transmission device 16 includes the engine 12 (here, the input shaft 22 which is an input rotating member for transmitting the power of the engine 12 as a driving force source also agrees) and the driving wheels 14 (here, to the driving wheels 14). A continuously variable transmission 24 and a gear mechanism 28 are provided in parallel with the output shaft 30 which is an output rotating member that outputs the power of the engine 12). Therefore, the power transmission device 16 transmits the power of the engine 12 to the first power transmission path for transmitting the power of the engine 12 from the input shaft 22 to the drive wheel 14 side (that is, the output shaft 30) via the stepless transmission 24. A second power transmission path for transmitting from the input shaft 22 to the drive wheel 14 side (that is, the output shaft 30) via the gear mechanism 28 is provided, and the first power transmission path and the second power transmission path thereof are provided according to the traveling state of the vehicle 10. It is configured so that it can be switched from the power transmission path. Therefore, the power transmission device 16 is a CVT that connects and disconnects the power transmission in the first power transmission path as a clutch mechanism that selectively (alternately) switches between the first power transmission path and the second power transmission path. It includes a traveling clutch C2, a forward clutch C1 for connecting and disconnecting power transmission in the second power transmission path, and a reverse brake B1. The CVT traveling clutch C2, the forward clutch C1, and the reverse brake B1 correspond to a disconnection / disconnection device, and all of them are hydraulic friction engagement devices (friction clutches) that are frictionally engaged by a hydraulic actuator. .. Further, the forward clutch C1 and the reverse brake B1 are each one of the elements constituting the forward / backward switching device 26, as will be described later. The continuously variable transmission 24 corresponds to the belt-type continuously variable transmission mechanism of the present invention, and the forward / backward switching device 26 and the gear mechanism 28 correspond to the gear-type transmission mechanism of the present invention. Further, the CVT traveling clutch C2 corresponds to the first clutch of the present invention, and the forward clutch C1 corresponds to the second clutch of the present invention.

The forward / backward switching device 26 is provided around the input shaft 22 in a coaxial center with respect to the input shaft 22, and is mainly composed of a double pinion type planetary gear device 26p, a forward clutch C1, and a reverse brake B1. Has been done. The carrier 26c of the planetary gear device 26p is integrally connected to the input shaft 22, the ring gear 26r of the planetary gear device 26p is selectively connected to the housing 18 via the reverse brake B1, and the sun gear 26s of the planetary gear device 26p is It is connected to a small diameter gear 42 provided around the input shaft 22 so as to be rotatable relative to the input shaft 22 in a coaxial center. Further, the carrier 26c and the sun gear 26s are selectively connected via the forward clutch C1. In the forward / backward switching device 26 configured in this way, when the forward clutch C1 is engaged and the reverse brake B1 is released, the input shaft 22 is directly connected to the small diameter gear 42, and the second power transmission path is described above. The power transmission path for forward movement is established (achieved) in. When the reverse brake B1 is engaged and the forward clutch C1 is released, the small diameter gear 42 is rotated in the opposite direction to the input shaft 22, and the reverse power is transmitted in the second power transmission path. The route is established. When both the forward clutch C1 and the reverse brake B1 are released, the second power transmission path is set to the neutral state (power transmission cutoff state) in which the power transmission is cut off.

The gear mechanism 28 includes a small-diameter gear 42 and a large-diameter gear 46 that is provided on the gear mechanism counter shaft 44 so as to be relatively non-rotatable and meshes with the small-diameter gear 42. Therefore, the gear mechanism 28 is a transmission mechanism in which one gear stage (gear ratio) is formed. An idler gear 48 is provided around the gear mechanism counter shaft 44 so as to be coaxially rotatable with respect to the gear mechanism counter shaft 44. Around the gear mechanism counter shaft 44, a meshing clutch D1 is further provided between the gear mechanism counter shaft 44 and the idler gear 48 to selectively connect and disconnect the gear mechanism counter shaft 44. Therefore, the meshing clutch D1 interrupts the power transmission in the second power transmission path provided in the power transmission device 16. Specifically, the meshing clutch D1 fits the first gear 50 formed on the gear mechanism counter shaft 44, the second gear 52 formed on the idler gear 48, and the first gear 50 and the second gear 52. It includes a hub sleeve 54 on which inner peripheral teeth that can be engaged (engaged and meshed) are formed. In the meshing clutch D1 configured in this way, the gear mechanism counter shaft 44 and the idler gear 48 are connected by fitting the hub sleeve 54 with the first gear 50 and the second gear 52. Further, the meshing clutch D1 further includes a known synchromesh mechanism S1 as a synchronization mechanism that synchronizes the rotation when the first gear 50 and the second gear 52 are fitted. The idler gear 48 meshes with an output gear 56 having a diameter larger than that of the idler gear 48. The output gear 56 is provided around the same rotation axis as the output shaft 30 so as not to rotate relative to the output shaft 30. When one of the forward clutch C1 and the reverse brake B1 is engaged and the meshing clutch D1 is engaged, the power of the engine 12 of the first power transmission path and the second power transmission path is input to the input shaft 22. A second power transmission path that is sequentially transmitted to the output shaft 30 via the forward / backward switching device 26, the gear mechanism 28, the idler gear 48, and the output gear 56 is selected.

The continuously variable transmission 24 is provided on a power transmission path between the input shaft 22 and the output shaft 30. The continuously variable transmission 24 includes a primary pulley 58, which is an input side member provided on the input shaft 22 and is a drive pulley having a variable effective diameter, and an output side member provided on a secondary shaft 60 coaxial with the output shaft 30. A secondary pulley 62 having a variable effective diameter and a transmission belt 64 wound between the pair of variable pulleys 58 and 62 are provided, and friction between the pair of variable pulleys 58 and 62 and the transmission belt 64 is provided. Power is transmitted via force. The output shaft 30 is arranged around the secondary shaft 60 so as to be rotatable relative to the secondary shaft 60 in a coaxial center.

In the primary pulley 58, the hydraulic pressure acting on the primary pulley 58 (that is, the primary pressure Pin supplied to the primary side hydraulic cylinder 58c) is regulated and controlled by the hydraulic control circuit 66 (see FIG. 3), so that each sheave 58a, The input side thrust (primary thrust) Win (= primary pressure Pin × pressure receiving area) in the primary pulley 58 for changing the V-groove width between 58b is controlled. Further, in the secondary pulley 62, the oil pressure acting on the secondary pulley 62 (that is, the secondary pressure Pout supplied to the secondary side hydraulic cylinder 62c) is regulated and controlled by the hydraulic control circuit 66, so that between the sheaves 62a and 62b. The output side thrust (secondary thrust) Wout (= secondary pressure Pout × pressure receiving area) in the secondary pulley 62 for changing the V-groove width is controlled. By controlling the primary thrust Win and the secondary thrust Wout, respectively, the V-groove width of each of the pulleys 58 and 62 is changed, the hook diameter (effective diameter) of the transmission belt 64 is changed, and the gear ratio (gear ratio) γ ( = Input shaft rotation speed Nin / Output shaft rotation speed Nout) is continuously changed, and the frictional force between each pulley 58, 62 and the transmission belt 64 (belt sandwiching) so that the transmission belt 64 does not slip. Pressure) is required and well controlled. By controlling each of the primary thrust Win and the secondary thrust Wout in this way, the actual gear ratio (actual gear ratio) γ is set as the target gear ratio γtgt while preventing the transmission belt 64 from slipping.

The CVT traveling clutch C2 is a drive wheel 14 side on the downstream side in the torque transmission path of the secondary pulley 62 (secondary shaft 60) (here, the secondary pulley 62 (secondary shaft 60)) which is an output side member of the continuously variable transmission 24. The output shaft 30 is also provided), and selectively connects and disconnects the secondary pulley 62 and the output shaft 30. In other words, the CVT traveling clutch C2 is provided between the secondary pulley 62 and the output shaft 30. Of the first power transmission path and the second power transmission path, the first power transmission path in which the power of the engine 12 is transmitted from the input shaft 22 to the output shaft 30 via the continuously variable transmission 24 is selected. Occasionally, the CVT traveling clutch C2 is engaged.

The operation of the power transmission device 16 will be described below. FIG. 2 is a diagram for explaining switching of the traveling pattern by using an engaging table of engaging elements for each traveling pattern of the power transmission device 16. In FIG. 2, C1 corresponds to the operating state of the forward clutch C1, C2 corresponds to the operating state of the CVT traveling clutch C2, B1 corresponds to the operating state of the reverse brake B1, and D1 corresponds to the meshing clutch D1. Corresponding to the operating state of, "○" indicates engagement (connection) and "x" indicates release (disconnection).

First, regarding gear traveling (also referred to as gear mode), which is a traveling pattern in which the power of the engine 12 is transmitted to the output shaft 30 via the gear mechanism 28 (that is, a traveling pattern in which power is transmitted through the second power transmission path). explain. In this gear mode, for example, the forward clutch C1 and the meshing clutch D1 are engaged, while the CVT traveling clutch C2 and the reverse brake B1 are released, as shown in FIG.

Specifically, when the forward clutch C1 is engaged, the planetary gear device 26p constituting the forward / backward switching device 26 is integrally rotated, so that the small diameter gear 42 is rotated at the same rotation speed as the input shaft 22. .. Further, since the small-diameter gear 42 is meshed with the large-diameter gear 46 provided on the gear mechanism counter shaft 44, the gear mechanism counter shaft 44 can be rotated in the same manner. Further, since the meshing clutch D1 is engaged, the gear mechanism counter shaft 44 and the idler gear 48 are connected. Since the idler gear 48 is meshed with the output gear 56, the output shaft 30 provided integrally with the output gear 56 is rotated. When the forward clutch C1 and the meshing clutch D1 are engaged in this way, the power of the engine 12 is sequentially transmitted to the output shaft via the torque converter 20, the forward / backward switching device 26, the gear mechanism 28, the idler gear 48, and the like. It is transmitted to 30. In this gear traveling, for example, when the reverse brake B1 and the meshing clutch D1 are engaged, while the CVT traveling clutch C2 and the forward clutch C1 are released, the reverse traveling is possible.

Next, CVT traveling (also referred to as belt mode), which is a traveling pattern in which the power of the engine 12 is transmitted to the output shaft 30 via the continuously variable transmission 24 (that is, a traveling pattern in which power is transmitted through the first power transmission path). I will explain. In this CVT running, for example, the CVT running clutch C2 is engaged, while the forward clutch C1, the reverse brake B1, and the meshing clutch D1 are released, as shown in the CVT running (high vehicle speed) of FIG. To.

Specifically, when the CVT traveling clutch C2 is engaged, the secondary pulley 62 and the output shaft 30 are connected, so that the secondary pulley 62 and the output shaft 30 are integrally rotated. When the CVT traveling clutch C2 is engaged in this way, the power of the engine 12 is sequentially transmitted to the output shaft 30 via the torque converter 20, the continuously variable transmission 24, and the like. The disengagement of the meshing clutch D1 during CVT traveling (high vehicle speed) eliminates dragging of the gear mechanism 28 or the like during CVT traveling, and prevents the gear mechanism 28 or the like from rotating at high vehicle speed. To do.

The gear running is selected in a low vehicle speed region including, for example, when the vehicle is stopped. If the gear ratio γ is defined as the rotation speed of the input shaft 22 / the rotation speed of the output shaft 30, the gear ratio γ1 (that is, the gear ratio EL formed by the gear mechanism 28) in the second power transmission path is a continuously variable transmission. It is set to a value larger than the maximum gear ratio (gear ratio on the lowest vehicle speed side) γmax formed by 24 (that is, the gear ratio on the low side). For example, the gear ratio γ1 corresponds to the first gear ratio γ1 which is the gear ratio of the first gear in the power transmission device 16, and the lowest gear ratio γmax of the continuously variable transmission 24 is the first gear in the power transmission device 16. It corresponds to the second speed gear ratio γ2, which is the gear ratio of the second gear. Gear running and CVT running are switched according to a shift line for switching between the first gear and the second gear in the shift map of the stepped transmission. Further, for example, in CVT traveling, a shift (for example, CVT shift, continuously variable transmission) in which the gear ratio γ is changed based on a traveling state such as an accelerator opening degree θacc and a vehicle speed V is executed.

For example, when switching from gear running to CVT running (high vehicle speed), the CVT running clutch C2 and the meshing clutch D1 are engaged from the state in which the forward clutch C1 and the meshing clutch D1 corresponding to the gear running are engaged. It is transiently switched to CVT running (medium vehicle speed) in the state of being clutched. That is, the CtoC shift is executed in which the forward clutch C1 is released and the clutch is changed so as to engage the CVT traveling clutch C2. At this time, the power transmission path is changed from the second power transmission path to the first power transmission path, and the power transmission device 16 is substantially upshifted. Then, after the power transmission path is switched, the meshing clutch D1 is released in order to prevent unnecessary dragging and high rotation of the gear mechanism 28 and the like (see the driven input cutoff in FIG. 2). In this way, the meshing clutch D1 functions as a driven input blocking clutch that cuts off the input from the drive wheel 14 side.

Further, for example, when switching from CVT traveling (high vehicle speed) to gear traveling, the meshing clutch D1 is further engaged in preparation for switching from the CVT traveling clutch C2 to the gear traveling. It is transiently switched to CVT driving (medium vehicle speed) (see downshift preparation in Fig. 2). In this CVT traveling (medium vehicle speed), the rotation is transmitted to the sun gear 26s of the planetary gear device 26p via the gear mechanism 28. When the CVT running clutch C2 is released from this CVT running (medium vehicle speed) state and the clutch is changed so as to engage the forward clutch C1 (for example, CtoC shifting), the gear running is switched to. .. At this time, the power transmission path is changed from the first power transmission path to the second power transmission path, and the power transmission device 16 is substantially downshifted.

FIG. 3 is a diagram illustrating a main part of a control function and a control system for shift control in the power transmission device 16. In FIG. 3, the vehicle 10 functions as a control device for the vehicle power transmission device of the present invention, for example, for switching the traveling pattern of the power transmission device 16 and controlling the continuously variable transmission of the continuously variable transmission 24. The electronic control device 100 including the above is provided. Therefore, FIG. 3 is a diagram showing an input / output system of the electronic control device 100, and is also a functional block diagram illustrating a main part of a control function by the electronic control device 100. The electronic control device 100 is configured to include, for example, a so-called microcomputer provided with a CPU, RAM, ROM, an input / output interface, etc., and the CPU follows a program stored in the ROM in advance while using the temporary storage function of the RAM. Various controls of the vehicle 10 are executed by performing signal processing. For example, the electronic control device 100 is designed to execute output control of the engine 12, shift control of the continuously variable transmission 24, belt pinching pressure control, control for switching a traveling pattern, and the like, and for engine control as needed. , For shift control, etc.

The electronic control device 100 is based on detection signals from various sensors included in the vehicle 10 (for example, various rotation speed sensors 82, 84, 86, accelerator opening sensor 88, throttle valve opening sensor 90, secondary rotation speed sensor 92, etc.). Corresponds to various actual values (for example, engine rotation speed Ne (rpm), turbine rotation speed Nt (rpm), input shaft rotation speed Nin (rpm), and vehicle speed V (km / h), which are the rotation speeds of the primary pulley 58. Output shaft rotation speed Nout (rpm), accelerator opening θacc (%), which is the amount of accelerator pedal operation as the driver's acceleration request amount, throttle valve opening θth (%), secondary which is the rotation speed of the secondary pulley 62. Rotation speed Nsec, etc.) are supplied respectively. The electronic control device 100 calculates the gear ratio γc (= input shaft rotation speed Nin / secondary rotation speed Nsec) of the continuously variable transmission 24 based on, for example, the input shaft rotation speed Nin and the secondary rotation speed Nsec.

Further, from the electronic control device 100, an engine output control command signal Se for output control of the engine 12, a hydraulic control command signal Sin, Sout for hydraulic control related to the speed change of the continuously variable transmission 24, and a power transmission device 16 The flood control command signals Sc1, Sb1, Sc2, Sd1 and the like for controlling the forward / backward switching device 26, the CVT traveling clutch C2, and the meshing clutch D1 related to the switching of the traveling pattern are output, respectively. Specifically, as the engine output control command signal Se, a throttle signal for driving the throttle actuator to control the opening and closing of the electronic throttle valve, an injection signal for controlling the amount of fuel injected from the fuel injection device, and the like. An ignition timing signal or the like for controlling the ignition timing of the engine 12 by the ignition device is output. Further, the hydraulic control command signal Sin is supplied to the actuator of the secondary pulley 62 as a command signal for driving the solenoid valve for adjusting the primary pressure Pin supplied to the actuator of the primary pulley 58, and the hydraulic control command signal Sout. A command signal or the like for driving the solenoid valve that regulates the secondary pressure Pout is output to the flood control circuit 66. Further, as the hydraulic control command signals Sc1, Sb1, Sc2, and Sd1, each hydraulic pressure acting on the forward clutch C1, the reverse brake B1, the CVT traveling clutch C2, and the meshing clutch D1 (that is, the forward clutch C1, the reverse clutch C1) A command signal for driving each solenoid valve that regulates the clutch pressure Pc1, clutch pressure Pb1, clutch pressure Pc2, clutch pressure Pd1) supplied to each actuator of the brake B1, CVT traveling clutch C2, and meshing clutch D1. Is output to the hydraulic control circuit 66.

In the hydraulic control circuit 66, the line pressure P1 is the hydraulic pressure that becomes the original pressure in pressure regulation control such as primary pressure Pin, secondary pressure Pout, clutch pressure Pc1, clutch pressure Pb1, clutch pressure Pc2, and clutch pressure Pd1. The line pressure P1 is regulated by a solenoid valve, for example, using the operating hydraulic pressure output (generated) from the oil pump 68 as the main pressure. In the hydraulic control circuit 66, for example, the primary pressure Pin and the secondary pressure Pout are controlled so as to generate a belt narrow pressure in the pulleys 58 and 62 that does not cause belt slippage and does not increase unnecessarily. Further, the gear ratio γc of the continuously variable transmission 24 is changed by changing the thrust ratio τ (= Wout / Win) of the pulleys 58 and 62 due to the mutual relationship between the primary pressure Pin and the secondary pressure Pout. For example, as the thrust ratio τ increases, the gear ratio γc increases (that is, the continuously variable transmission 24 is downshifted).

The electronic control device 100 outputs an engine output control command signal Se to a throttle actuator, a fuel injection device, and an ignition device, respectively, for controlling the output of the engine 12, for example. The electronic control device 100 calculates the required driving force Fdem as the driving required amount by the driver based on the actual accelerator opening θacc and the vehicle speed V, for example, from a predetermined relationship (driving force map). The target engine torque Tetgt for obtaining the required driving force Fdem is set, and the electronic throttle valve is opened and closed by the throttle actuator so that the target engine torque Tetgt can be obtained. In addition, the fuel injection amount is controlled by the fuel injection device. , The ignition timing is controlled by the ignition device.

The electronic control device 100 includes a shift control unit 102. The shift control unit 102 includes a CtoC shift determination unit 104, a belt input torque calculation unit 106, a thrust control unit 110, and a CtoC shift control unit 112.

The shift control unit 102 prevents, for example, belt slippage of the continuously variable transmission 24 in CVT traveling in the belt mode (CVT mode) in which the first power transmission path is established via the continuously variable transmission 24. In order to achieve the target gear ratio γtgt of the continuously variable transmission 24, the primary indicator pressure Pindir as the command value of the primary pressure Pin is set as the hydraulic control command signal Sin based on the actual belt input torque and the gear ratio γc, and the secondary pressure. The secondary instruction pressure Poutdir as the command value of Pout is output to the flood control circuit 66 as the flood control command signal Sout, and the CVT shift is executed.

The CtoC shift determination unit 104 has an upshift line and a downshift for switching between the first gear ratio γ1 corresponding to the gear ratio EL in gear running and the second gear ratio γ2 corresponding to the lowest gear ratio γmax in CVT running. Using the shift line, the shift (switching of the gear ratio) is determined based on the vehicle speed V and the accelerator opening degree θacc, and based on the determination result, it is determined whether or not to switch the traveling pattern while the vehicle is traveling. The upshift line and the downshift line are, for example, predetermined shift lines and have a predetermined hysteresis.

When the CtoC shift determination unit 104 determines the upshift during gear travel, the CtoC shift control unit 112 switches from the gear mode to the CVT travel mode (high vehicle speed). When switching from the gear mode to the CVT travel mode, the CtoC shift control unit 112 first releases the forward clutch C1 and executes an upshift by the CtoC shift that engages the CVT travel clutch C2. The CtoC shift control unit 112 uses the clutch instruction pressure Pc2dir, which is the engagement element instruction pressure for obtaining the torque capacity Tc2 of the CVT traveling clutch C2, which is the engagement element, as the hydraulic control command signal Sc2, and the hydraulic control command signal Sc1. The clutch instruction pressure Pc1dir, which is the release element instruction pressure for obtaining the torque capacity Tc1 of the forward clutch C1 which is the release element, is output to the flood control circuit 66, respectively. This state corresponds to the transiently switched CVT running (medium vehicle speed) in FIG. 2, and the power transmission path in the power transmission device 16 is a second power transmission path in which power is transmitted via the gear mechanism 28. To the first power transmission path in which power is transmitted via the continuously variable transmission 24. Further, from the viewpoint of the continuity of the change of the gear ratio γ accompanying the switching from the gear mode to the CVT driving mode, the gear ratio γc of the continuously variable transmission 24 is, for example, to the lowest gear ratio γmax side during the upshift by the CtoC shift. It is controlled to be maintained. Next, the CtoC shift control unit 112 outputs a hydraulic control command signal Sd1 that operates the hub sleeve 54 so as to release the engaged clutch D1, and switches to CVT traveling (high vehicle speed). The hub sleeve 54 is driven by a hydraulic actuator (not shown), and the pressing force on the hub sleeve 54 is adjusted by the clutch pressure Pd1 supplied to the hydraulic actuator. In this CVT traveling, the shift control unit 102 targets, for example, the oil pressure at which the torque capacity Tc2 of the CVT traveling clutch C2 exceeds the transmission torque corresponding to the input torque Tin that needs to be transmitted in the first power transmission path. Set the clutch pressure Pc2tgt. The shift control unit 102 outputs the clutch instruction pressure Pc2dir as the flood control command signal Sc2 to the flood control circuit 66 so that the target clutch pressure Pc2tgt can be obtained. The hydraulic control circuit 66 operates each solenoid valve in accordance with the hydraulic control command signal Sc2 to adjust the clutch pressure Pc2.

Further, when the CtoC shift control unit 112 determines the downshift by the CtoC shift determination unit 104 during CVT travel (high vehicle speed), the CtoC shift control unit 112 first engages the hub sleeve 54 so as to engage the meshing clutch D1 being released. The hydraulic control command signal Sd1 to be operated is output to switch to the CVT driving mode (medium vehicle speed). Next, the CtoC shift control unit 112 executes a downshift by releasing the CVT traveling clutch C2 and engaging the forward clutch C1 with the CtoC shift. The CtoC shift control unit 112 releases the clutch instruction pressure Pc1dir, which is the engagement element instruction pressure for obtaining the torque capacity Tc1 of the forward clutch C1 which is the engagement element, as the hydraulic control command signal Sc1, and the clutch instruction pressure Pc1dir as the hydraulic control command signal Sc2. The clutch instruction pressure Pc2dir, which is the release element instruction pressure for obtaining the torque capacity Tc2 of the CVT traveling clutch C2, which is an element, is output to the flood control circuit 66, respectively. This state corresponds to the gear mode of FIG. 2, and the power transmission path in the power transmission device 16 is powered from the first power transmission path through which power is transmitted via the continuously variable transmission 24 via the gear mechanism 28. Is switched to the second power transmission path through which is transmitted. The downshift due to the CtoC shift may be performed at the same time as the downshift of the continuously variable transmission 24, for example, when a large acceleration operation is performed by the driver. As described above, when the CtoC shift control unit 112 switches from the power transmission via the continuously variable transmission 24 to the power transmission via the gear mechanism 28 while the vehicle 10 is traveling, the CtoC shift control unit 112 engages the meshing clutch D1 on the engaging side. Then, the CVT traveling clutch C2 is released. In this gear traveling, the shift control unit 102 sets the target clutch to a hydraulic pressure such that the torque capacity Tc1 of the forward clutch C1 exceeds the transmission torque corresponding to the input torque Tin that needs to be transmitted in the second power transmission path. Set the pressure Pc1tgt. The shift control unit 102 outputs the clutch instruction pressure Pc1dir as the hydraulic control command signal Sc1 to the hydraulic control circuit 66 so that the target clutch pressure Pc1tgt can be obtained. The hydraulic control circuit 66 operates each solenoid valve in accordance with the hydraulic control command signal Sc1 to adjust the clutch pressure Pc1.

In the CVT travel mode, the belt input torque calculation unit 106 sets the input torque Tin of the stepless transmission 24, which is the belt input torque input to the primary pulley 58, from a predetermined relationship (for example, an engine torque map). An estimated value of engine torque Te is calculated based on the opening degree θth and engine rotation speed Ne, and the input torque Tin of the stepless transmission 24 is calculated based on the engine torque Te and the torque amplification factor of the torque converter 20.

Further, when the CtoC shift determination unit 104 determines that the CtoC shift is being executed, the belt input torque calculation unit 106 determines, for example, the clutch instruction pressure Pc2dir and the secondary side hydraulic cylinder 62c that are output to the hydraulic control circuit 66. Based on the specifications, the torque capacity Tc2 of the CVT traveling clutch C2 during CtoC shifting is calculated. Instead of the clutch indicated pressure Pc2dir, the clutch pressure Pc2 may be directly detected by a hydraulic sensor or the like. Next, the belt input torque calculation unit 106 engages the CVT traveling clutch C2 and releases the forward clutch C1. When the upshift is in progress due to the CtoC shift, the torque of the CVT traveling clutch C2 during the CtoC shift is in progress. The first calculated value obtained by dividing the capacity Tc2 by the gear ratio γc of the continuously variable transmission 24 during CtoC shifting and the lower limit guard value obtained by dividing the drag torque of the CVT traveling clutch C2 by the gear ratio γc of the continuously variable transmission 24. The larger value is set to the belt slip limit thrust calculation input torque (minimum guaranteed belt input torque) Tlmtc. Here, since the torque capacity Tc2 of the CVT traveling clutch C2 during CtoC shifting includes an inertia shuttle based on a change in the gear ratio γ during CtoC shifting, the first calculated value is preferably CtoC. Inertia shuttle torque during shifting is considered. Further, when the belt input torque calculation unit 106 releases the CVT traveling clutch C2 and is in the downshift due to the CtoC shifting that engages the forward clutch C1, the torque of the CVT traveling clutch C2 during the CtoC shifting is in progress. The smaller value of the first calculated value obtained by dividing the capacitance Tc2 by the gear ratio γc of the continuously variable transmission 24 during CtoC shifting and the turbine torque Tt is set as the input torque Tlmtc for calculating the belt slip limit thrust. The input torque Tlmtc for calculating the belt slip limit thrust is the input of the continuously variable transmission 24 used to calculate the belt slip limit thrust Wlmtc, which is the minimum thrust necessary to guarantee the suppression of belt slip during CtoC shifting. Torque Tin.

Further, the belt input torque calculation unit 106 sets the first calculated value to the thrust ratio calculation torque Tinc during the upshift due to the CtoC shift. Further, the belt input torque calculation unit 106 sets the smaller of the turbine torque Tt and the first calculated value to the thrust ratio calculation input torque Tinc during the downshift due to the CtoC shift. The thrust ratio calculation input torque Tin is the input torque Tin of the continuously variable transmission 24 used to calculate the shift thrust ratio τ of the continuously variable transmission 24 during CtoC shifting.

The thrust control unit 110 considers the calculation of the target secondary thrust Wouttgt and the target primary thrust Wintgt, and the thrust (required thrust) required to prevent the belt slip with the minimum necessary thrust, that is, immediately before the belt slip occurs. The belt slip limit thrust (hereinafter referred to as slip limit thrust) Wlmt, which is the thrust and guarantees that belt slip does not occur, is calculated. The belt slip limit thrust Wlmt includes a primary side slip limit thrust Wlmtin and a secondary side slip limit thrust Wlmtout. The primary side slip limit thrust Wlmtin and the secondary side slip limit thrust Wlmtout are the input torque Tin of the continuously variable transmission 24 and the secondary pulley as the input torque of the primary pulley 58 from the following equations (1) and (2), respectively. Output torque Tout (= γ × Tin) of continuously variable transmission 24 as input torque of 62, sheave angle (cone surface angle) α of each pulley 58, 62, predetermined belt element-sive friction coefficient μ, actual speed change Propulsion based on the belt hook diameter Rin on the primary pulley 58 side uniquely calculated from the ratio γ and the belt hook diameter Rout on the secondary pulley 62 side uniquely calculated from the actual shift ratio γ (see FIG. 1 above). Calculated by the control unit 110. The input torque Tin here is calculated by the belt input torque calculation unit 106 from the engine torque Te and the torque amplification factor during the CVT traveling mode.
Wlmtin = (Tin × cosα) / (2 × μ × Rin)… (1)
Wlmtout ＝ (Tout × cosα) / (2 × μ × Rout)… (2)

Further, the thrust control unit 110 has a larger value of the first calculated value and the lower limit guard value during the upshift due to the CtoC shift during the CtoC shift, and the turbine torque during the downshift due to the CtoC shift. The smaller of Tt and the first calculated value is the above equation (1) and the above (2) based on the belt slip limit thrust calculation input torque (minimum guaranteed belt input torque) Tlmtc set respectively. The belt slip limit thrust Wlmt is calculated from the equation.

The thrust control unit 110 calculates the target input shaft rotation speed Nitgt based on the accelerator opening θacc and the vehicle speed V from a predetermined relationship (for example, a CVT shift map), and the target shift based on the target input shaft rotation speed Nitgt. The ratio γtgt (= Nitgt / Nout) is calculated. Then, the thrust control unit 110 calculates the thrust ratio τ for constantly maintaining the target gear ratio γtgt based on the target gear ratio γtgt and the torque ratio from a predetermined relationship (thrust ratio map). The above torque ratio is a ratio (= Tin / Tlmtin) of the calculated input torque Tin and the guaranteed input torque Tlmtin, which is the limit torque that can be input to the predetermined continuously variable transmission 24. Here, the thrust ratio map has a relationship that, if the torque ratios are the same, the thrust ratio τ increases as the target gear ratio γtgt increases. Further, in the thrust ratio map, if the target gear ratio γtgt is the same, the torque ratio is relatively close to 1 in the driving state in which the drive wheels 14 are driven by the driving force of the engine 12 having a torque ratio of 0 to 1. In the region excluding the region of the high torque ratio, the thrust ratio τ becomes larger as the torque ratio approaches 0 (zero value). Therefore, when the input torque Tin is zero value, that is, the torque ratio is zero value in the driving state, the thrust ratio τ becomes the maximum value for any target gear ratio γtgt.

Further, the thrust control unit 110 has the first calculated value during the upshift due to the CtoC shift, and the turbine torque Tt and the smaller of the first calculated values during the downshift due to the CtoC shift, respectively. The torque ratio is calculated from the set thrust ratio calculation torque (shift input torque) Tinc. The thrust control unit 110 calculates the thrust ratio τc for shifting from the thrust ratio map based on the torque ratio and the target gear ratio γtgt.

The thrust control unit 110 calculates the target secondary thrust Wouttgt and the target primary thrust Wintgt for achieving this thrust ratio τ. For example, the thrust control unit 110 is on the secondary pulley 62 side required for shift control based on the primary side slip limit thrust Wlmtin, which is the slip limit thrust on the primary pulley 58 side, and the thrust ratio τ that realizes the target gear ratio γtgt. Calculates the secondary shift control thrust Woutsh, which is the thrust of. The thrust control unit 110 sets the larger of the secondary side slip limit thrust Wlmtout, which is the slip limit thrust on the secondary pulley 62 side, and the calculated secondary side shift control thrust Woutsh, as the target secondary thrust Wouttgt. The thrust control unit 110 calculates the target primary thrust Wintgt based on the target secondary thrust Wouttgt and the thrust ratio τ.

Further, the thrust control unit 110 sets the target primary thrust Wintgt and the target secondary thrust Wouttgt during the CtoC shift from the belt slip limit thrust Wlmt during the CtoC shift and the shift thrust ratio τc that realizes the target shift ratio γtgt. That is, the thrust unit 110 has a larger value of the first calculated value and the lower limit guard value during the upshift during the CtoC shift, and the turbine torque Tt and the first thrust during the downshift during the CtoC shift. The smaller of the calculated values is the primary side slip limit thrust Wlmtin calculated from the above equation (1) based on the input torque Tlmtc for calculating the belt slip limit thrust set respectively, and the primary side slip limit thrust Wlmtin. And, the secondary side shift control thrust Woutsh is calculated based on the shift thrust ratio τc. The thrust control unit 110 sets the larger value of the secondary side shift control thrust Woutsh and the secondary side slip limit thrust Wlmtout to the target secondary thrust Wouttgt, and based on the target secondary thrust Wouttgt and the shift thrust ratio τc, The target primary thrust Wintgt is calculated to control the narrow belt pressure of the continuously variable transmission 24. However, if the lower limit guard value is set to the input torque Tlmtc for calculating the belt slip limit thrust during the upshift by CtoC shifting, the lower limit thrust Wlmtcmin is set for the belt slip limit thrust Wlmt (secondary side slip limit thrust Wlmtout). To. This lower limit thrust Wlmtcmin is a CtoC shift depending on the belt slip limit thrust Wlmt (secondary side slip limit thrust Wlmtout) calculated based on the first calculated value due to the drag of the CVT traveling clutch C2 and the inertia of the secondary pulley 62. It is set in advance in order to prevent the belt slip of the continuously variable transmission 24 during the upshift due to the above cannot be guaranteed.

The thrust control unit 110 sets the target secondary thrust Wouttgt and the target primary thrust Wintgt as the target secondary pressure Pouttgt (= Wouttgt / 62c pressure receiving area) and the target primary pressure Pintgt (=) based on the respective pressure receiving areas of the hydraulic cylinders 62c and 58c. It is converted to the pressure receiving area of Wintgt / 58c). The thrust control unit 110 uses the primary instruction pressure Pindir as the hydraulic control command signal Sin and the secondary instruction pressure Poutdir as the hydraulic control command signal Sout so that the target primary pressure Pintgt and the target secondary pressure Pouttgt can be obtained. Output to. The hydraulic control circuit 66 operates each solenoid valve according to the hydraulic control command signals Sin and Sout to adjust the primary pressure Pin and the secondary pressure Pout. As a result, in the CVT traveling mode, for example, the CVT shift is executed so as to achieve the target gear ratio γtgt of the continuously variable transmission 24 while preventing the belt slip of the continuously variable transmission 24 from occurring.

While traveling in the gear mode in which the second power transmission path is established via the gear mechanism 28, the continuously variable transmission 24 is connected to the input shaft 22 with the secondary shaft 60 separated from the output shaft 30. It is idled as the pulley 58 rotates. On the other hand, the shift control unit 102 sets the gear ratio γc of the continuously variable transmission 24 to the lowest gear ratio when the continuously variable transmission 24 is idling in the gear mode from the viewpoint of continuity in switching from gear travel to CVT travel. The primary pressure Pin and the secondary pressure Pout are controlled to the hydraulic pressure controlled to γmax (that is, the hydraulic pressure at which the primary thrust Win and the secondary thrust Wout for achieving the lowest gear ratio γmax are obtained). On the other hand, the shift control unit 102 suppresses the input shaft inertial loss due to the rotation fluctuation of the input shaft 22 when the continuously variable transmission 24 is idling in the gear mode from the viewpoint of the power performance (drivability) of the vehicle 10. Therefore, the primary is to the minimum hydraulic pressure that does not cause the transmission belt 64 to slip with respect to the input torque Tin to the continuously variable transmission 24 (that is, the primary side slip limit thrust Wlmtin and the secondary side slip limit thrust Wlmtout). The pressure Pin and the secondary pressure Pout are controlled.

FIG. 4 shows a control function of the electronic control device 100 of the present embodiment in thrust control of the continuously variable transmission 24 during CtoC shifting, and a control function of a comparative example having a control function different from that of the electronic control device 100 of the present embodiment. It is a figure which shows respectively. The target secondary thrust Wouttgt and the target primary thrust Wintgt used for the thrust control of the continuously variable transmission 24 during the CtoC shift shown in the comparative example in FIG. 4 are calculated as follows. First, the base engine torque Te is set in the belt slip limit thrust calculation input torque (minimum guaranteed belt input torque) Tlmtc as the input torque Tin of the continuously variable transmission 24 during CtoC shifting. Then, based on the input torque Tlmtc for calculating the belt slip limit thrust (minimum guaranteed belt input torque Tlmtc) in which the engine torque Te is set, the belt slip limit thrust Wlmt (primary side slip limit thrust Wlmtin) is obtained from the above equation (1). , Calculated during CtoC shifting. The disturbance guaranteed thrust is added to the primary side slip limit thrust Wlmtin calculated in this way, and the belt thrust after the disturbance guarantee is calculated. After disturbance guarantee, the belt thrust is the thrust corresponding to the base engine torque Te plus the thrust corresponding to the maximum inner shuttlek during CtoC shifting (disturbance guaranteed thrust) in order to suppress the belt slip during CtoC shifting. Is. Here, the maximum inertia torque is the inertia torque when the time change rate (dγ / dt) of the gear ratio γ is maximum during CtoC shifting. Therefore, the belt thrust after the disturbance guarantee becomes a value larger than the belt slip limit thrust Wlmt set based on the minimum guaranteed belt input torque Tlmtc in which the base engine torque Te is set during CtoC shifting.

Further, in the comparative example of FIG. 4, during the CtoC shift, the continuously variable transmission 24 is downshifted to the lowest gear ratio γmax side, so that the target gear ratio γtgt of the continuously variable transmission 24 is the lowest gear ratio γmax. Is set to. Further, in order to guarantee a downshift of the continuously variable transmission 24 to the lowest gear ratio γmax side, the thrust ratio calculation torque Tinc is set to no load (zero value). Based on the thrust ratio calculation torque Tinc and the lowest shift ratio γmax, the shift thrust ratio τc during CtoC shift is calculated from the thrust ratio map. The secondary side shift control thrust Woutsh is calculated from the belt thrust after disturbance guarantee and the shift thrust ratio τc, and the larger value of the secondary side shift control thrust Woutsh and the secondary side slip limit thrust Wlmtout becomes the target secondary thrust Wouttgt. Set. The target primary thrust Wintgt is calculated based on the target secondary thrust Wouttgt and the shift thrust ratio τc.

When controlled as in the comparative example of FIG. 4, the engine torque Te is set in the input torque Tlmtc for calculating the belt slip limit thrust as the input torque Tin of the stepless transmission 24 during CtoC shifting, and the belt slip limit thrust is calculated. The disturbance guaranteed thrust is added to the primary side slip limit thrust Wlmtin calculated based on the input torque Tlmtc, and the belt thrust after the disturbance guarantee is calculated. The target secondary thrust Wouttgt calculated during CtoC shifting based on the belt thrust after the disturbance guarantee is compared with the target secondary thrust Wouttgt calculated based on the primary side slip limit thrust Wlmtin without the disturbance guaranteed thrust, for example. Since the maximum inner shuttle torque during CtoC shifting is uniformly increased, belt slippage of the continuously variable transmission 24 is suppressed during CtoC shifting. However, the target secondary thrust Wouttgt in the comparative example does not reflect the actual input torque Tin of the continuously variable transmission 24 during CtoC shifting. Therefore, based on the disturbance guaranteed thrust after the disturbance guarantee is added to the primary side slip limit thrust Wlmtin based on the input torque for calculating the belt slip limit thrust (minimum guaranteed belt input torque) Tlmtc in which the engine torque Te is set. Compare the secondary pressure Pout that achieves the set target secondary thrust Wouttgt with the secondary pressure Pout required to achieve the target secondary thrust Wouttgt that is set based on the actual input torque Tin of the stepless transmission 24. And there is a possibility that it will be excessive. As a result, an extra drive torque for driving the oil pump 68 is required, which may cause a problem of reduced fuel consumption. Further, in the comparative example of FIG. 4, the thrust ratio calculation torque Tinc set to no load (zero value) in order to guarantee the downshift of the continuously variable transmission 24 to the lowest gear ratio γmax during CtoC shifting. The shift thrust ratio τc is calculated based on. Therefore, the shift thrust ratio τc for calculating the balance thrust for maintaining the lowest gear ratio γmax of the continuously variable transmission 24 during CtoC shift becomes the maximum value. As a result, when controlled as in the comparative example of FIG. 4, the continuously variable transmission 24 is stepless as compared with the case where the shifting thrust ratio τc is set according to the actual input torque Tin of the continuously variable transmission 24, for example. The thrust ratio for calculating the balance thrust for maintaining the lowest gear ratio γmax of the transmission 24 becomes larger (the pressing force (narrow pressure) toward the lowest gear ratio side becomes larger), and the primary pressure Pin is required. Since the above reduction is achieved, there is a possibility that after the completion of the upshift by the CtoC shift, the start of the upshift from the lowest gear ratio γmax of the continuously variable transmission 24 is delayed and the shift performance is deteriorated. is there.

FIG. 5 is a flowchart illustrating a main part of the control operation of the electronic control device 100. FIG. 6 shows an example of the control operation of the electronic control device 100 of the present embodiment and an example of the control operation of the electronic control device of the comparative example having a control function different from that of the electronic control device 100 in the upshift by the CtoC shift. Is a time chart showing each. In FIG. 6, the gear ratios γc of the secondary pressure Pout, the primary pressure Pin, and the continuously variable transmission 24 in the examples and the comparative examples are shown by solid lines and broken lines, respectively. Further, the torque for calculating the thrust ratio (input torque for calculating the thrust ratio) Tinc shown by the solid line is also the first calculated value obtained by dividing the torque capacity Tc2 of the CVT traveling clutch C2 by the gear ratio γc of the continuously variable transmission 24. is there. In FIG. 5, in step S1 corresponding to the function of the CtoC shift determination unit 104 (hereinafter, “step” is omitted), it is determined whether or not CtoC shift is in progress. When the determination of S1 is denied, that is, during gear running in the gear mode (before t1 in FIG. 6) or during CVT running in the CVT mode (belt mode) (after t3 in FIG. 6), the belt is input. In S5 corresponding to the function of the torque calculation unit 106, the input torque Tin of the continuously variable transmission 24 is set according to the gear mode or the belt mode. After executing S5, S6 is executed. On the other hand, when the determination of S1 is affirmed (from t1 to t3 in FIG. 6), in S2 corresponding to the function of the CtoC shift determination unit 104, the forward clutch C1 is released and the CVT traveling clutch C2 is released. It is determined whether or not an upshift is being performed due to the engaged CtoC shift. When the determination of S2 is affirmed (from t1 to t3 in FIG. 6), the torque capacity Tc2 of the CVT traveling clutch C2 is set to the continuously variable transmission 24 in S3 corresponding to the function of the belt input torque calculation unit 106. The larger of the first calculated value divided by the gear ratio γc of the continuously variable transmission and the lower limit guard value obtained by dividing the torque capacity Tc2 of the CVT traveling clutch C2 by the gear ratio γc of the continuously variable transmission 24 is none during CtoC shifting. The input torque Tlmtc (TQ1) for calculating the belt slip limit thrust as the input torque Tin (belt input torque) of the speed transmission 24 is set. Here, the torque capacity Tc2 of the CVT traveling clutch C2 is calculated by the clutch instruction pressure Pc2dir or the like. In FIG. 6, between the time t1 and the time t2, the lower limit guard value indicated by the alternate long and short dash line, which is larger than the first calculated value indicated by the solid line, is the input torque for calculating the belt slip limit thrust indicated by the alternate long and short dash line. It is set to Wlmtc, and the first calculated value larger than the lower limit guard value is set to the belt slip limit thrust calculation input torque Tlmtc between the time t2 and the time t3. Further, in S3, the first calculated value is set to the thrust ratio calculation torque Tinc (TQ2) (from t1 time point to t3 time point in FIG. 6). In FIG. 6, the belt slip limit thrust calculation input torque Tlmtc is shown slightly deviated from the first calculated value (thrust ratio calculation input torque Tinc) and the lower limit guard value. After executing S3, S6 and below are executed. When the determination of S2 is denied, that is, when the CVT traveling clutch C2 is released and the downshift is in progress due to the CtoC shift that engages the forward clutch C1, S4 corresponding to the function of the belt input torque calculation unit 106. The smaller (minimum) of the first calculated value obtained by dividing the torque capacity Tc2 of the CVT traveling clutch C2 by the gear ratio γc of the continuously variable transmission 24 and the turbine torque Tt is the continuously variable transmission during CtoC shifting. The input torque Tlmtc for calculating the belt slip limit thrust as the input torque Tin (belt input torque) of the transmission 24 is set. Further, in S4, the smaller (minimum) of the first calculated value and the turbine torque Tt is set in the thrust ratio calculation torque Tinc. After executing S4, S6 and below are executed.

In S6 corresponding to the function of the thrust control unit 110, the belt slip limit thrust Wlmt is calculated from the belt slip limit thrust calculation input torque (minimum guaranteed belt input torque) Tlmtc based on the above equations (1) and (2). It is calculated. In S7 corresponding to the function of the thrust control unit 110, the thrust ratio τc for shifting is calculated from the thrust ratio calculation torque Tinc based on the thrust ratio map during CtoC shifting. In S8 corresponding to the function of the thrust control unit 110, first, the secondary side shift control thrust Woutsh is calculated from the primary side slip limit thrust Wlmtin and the shift thrust ratio τc. Then, the larger value of the secondary side shift control thrust Woutsh and the secondary side slip limit thrust Wlmtout is set as the target secondary thrust Wouttgt that suppresses the belt slip of the continuously variable transmission 24. That is, when the first calculated value is set as the input torque Tin of the continuously variable transmission 24 during an upshift due to a CtoC shift or a downshift due to a CtoC shift (from t2 to t3 in FIG. 6). , The secondary pressure Pout for achieving the belt narrow pressure corresponding to the input torque Tin of the continuously variable transmission 24 during the CtoC shift is calculated. However, when the lower limit guard value is set to the input torque Tlmtc for calculating the belt slip limit thrust during upshifting due to CtoC shifting (from t1 to t2 in FIG. 6), the drag of the CVT traveling clutch C2 The secondary pressure Pout is calculated from the lower limit thrust (lower limit guard) Wlmtcmin in consideration of the inertia of the secondary pulley 62 and the lower limit thrust (lower limit guard). On the other hand, in the comparative example of FIG. 6, since the secondary pressure Pout is calculated from the target secondary thrust Wouttgt calculated based on the belt thrust after the disturbance guarantee, it is higher than the secondary pressure Pout of the embodiment during CtoC shifting. (From t1 to t3 in FIG. 6). In S9 corresponding to the function of the thrust control unit 110, the target primary thrust Wintgt is calculated from the target secondary thrust Wouttgt and the shift thrust ratio τc, and the primary pressure Pin is calculated from the target primary thrust Wintgt. The primary instruction pressure Pindir and the secondary instruction pressure Poutdir are output to the flood control circuit 66 so that the target primary pressure Pintgt and the target secondary pressure Pouttgt can be obtained. Thereby, the primary thrust Win and the secondary thrust Wout are controlled so as to guarantee the suppression of the belt slip of the continuously variable transmission 24 during the CtoC shift. After executing S9, this flowchart is terminated.

In the comparative example of FIG. 6, in order to achieve the lowest gear ratio γmax during CtoC shifting, the thrust ratio calculation torque Tinc is set to no load, and the primary pressure Pin indicated by the broken line is set to the minimum pressure. .. On the other hand, in this embodiment, since the thrust ratio τc for shifting is calculated based on the thrust ratio calculating torque Tinc that reflects the actual input torque Tin, the lowest gear ratio γmax, which is the target gear ratio γtgt, is set. The primary pressure Pin shown by the solid line is set from the appropriate balanced thrust to achieve. In both the examples and the comparative examples, the gear ratio γc of the continuously variable transmission 24 during the upshift by the CtoC shift is maintained at the lowest gear ratio γmax (from t1 to t3 in FIG. 6). After the end of the upshift by the CtoC shift (after t3 in FIG. 6), the actual gear ratio γc shown by the solid line with respect to the target gear ratio γtgt in the upshift from the lowest gear ratio γmax of the continuously variable transmission 24 in the embodiment. Compared with the followability of the actual gear ratio γc shown by the broken line with respect to the target gear ratio γtgt of the continuously variable transmission 24 in the comparative example in which the primary pressure Pin was lowered more than necessary during the CtoC shift. And it is improving.

As described above, according to the electronic control device 100 of the present embodiment, the belt input torque calculation unit 106 engages the CVT traveling clutch C2 and releases the forward clutch C1 during the upshift by the CtoC shift. The larger value of the first calculated value obtained by dividing the torque capacity Tc2 of the CVT traveling clutch C2 by the gear ratio γc of the continuously variable transmission 24 and the lower limit guard value is set as the input torque Tin to the continuously variable transmission 24. The belt slip limit thrust Wlmt is set, and the first calculated value is set to the input torque Tinc for calculating the thrust ratio. Further, the belt input torque calculation unit 106 sets the torque capacity Tc2 of the CVT traveling clutch C2 to the continuously variable transmission 24 during the downshift by the CtoC shifting that engages the forward clutch C1 and releases the CVT traveling clutch C2. The first calculated value divided by the gear ratio γc and the smaller value of the turbine torque Tt are the input torque Tlmtc for calculating the belt slip limit thrust as the input torque Tin to the continuously variable transmission 24 and the torque for calculating the thrust ratio. Set to Tinc. The thrust control unit 110 calculates the belt slip limit thrust Wlmt during CtoC shifting from the belt slip limit thrust calculation input torque (minimum guaranteed belt input torque) Tlmtc based on the above equations (1) and (2). The thrust control unit 110 calculates the shift thrust ratio τc from the thrust ratio calculation torque Tinc based on the thrust ratio map. Then, the thrust control unit 110 sets the target primary thrust Wintgt and the target secondary thrust Wouttgt from the belt slip limit thrust Wlmt and the shift thrust ratio τc, and controls the belt narrow pressure of the continuously variable transmission 24 during CtoC shift. .. Therefore, the belt narrow pressure for suppressing the belt slip can be set to a necessary and sufficient value according to the actual input torque Tin of the continuously variable transmission 24 that changes transiently during the CtoC shift. As a result, for example, the target secondary thrust Wouttgt is calculated from the disturbance guaranteed thrust after adding the disturbance guaranteed thrust to the primary side slip limit thrust Wlmtin calculated based on the engine torque Te in consideration of the maximum inner shuttlek during CtoC shifting. Compared with the comparative example, the excess of the secondary pressure Pout for the thrust control of the continuously variable transmission 24 during the CtoC shift can be suppressed, and the decrease in fuel consumption can be suppressed.

Further, according to the electronic control device 100 of the present embodiment, when the first calculated value is smaller than the turbine torque Tt during the upshift by the CtoC shift and the downshift by the CtoC shift, the first calculation is performed. The value is set to the thrust ratio calculation torque Tinc for calculating the shift thrust ratio τc. Therefore, in this embodiment, the primary pressure is derived from the shift thrust ratio τc calculated from the thrust ratio calculation torque Tinc that reflects the actual input torque Tin in order to achieve the balanced thrust that maintains the lowest shift ratio γmax. Since the Pin is calculated, the primary pressure Pin is, for example, the thrust ratio for calculating the thrust ratio, which is set to no load (zero value), and the thrust ratio for shifting to achieve the balanced thrust that maintains the lowest gear ratio γmax. It is larger than the primary pressure Pin of the comparative example in which τc is the maximum value. As a result, the delay in starting the upshift of the continuously variable transmission 24 from the lowest gear ratio γmax after the upshift due to the CtoC shift is suppressed, and the shift performance is improved.

Although the present invention has been described in detail with reference to the tables and drawings above, the present invention can be carried out in still another embodiment, and various modifications can be made without departing from the gist thereof.

For example, in the above-described embodiment, the gear mechanism 28 is a transmission mechanism in which one gear stage is formed, but the present invention is not limited to this. For example, the gear mechanism 28 may be a transmission mechanism in which a plurality of gear stages having different gear ratios γ are formed. That is, the gear mechanism 28 may be a stepped transmission that shifts in two or more gears.

It should be noted that the above description is merely an embodiment, and other examples are not given, but the present invention shall be carried out in a mode in which various changes and improvements are made based on the knowledge of those skilled in the art without departing from the gist thereof. Can be done.

12: Engine (driving force source)
14: Drive wheel 16: Power transmission device 22: Input shaft (input rotating member)
24: Continuously variable transmission (belt type continuously variable transmission mechanism)
28: Gear mechanism (gear type electric transmission mechanism)
30: Output shaft (output rotating member)
60: Secondary shaft (output side member)
62: Secondary pulley (output side member)
100: Electronic control device (control device for vehicle power transmission device)
C1: Forward clutch (clutch mechanism, second clutch)
C2: CVT running clutch (clutch mechanism, first clutch)

Claims (1)

The power from the driving force source is transmitted via the torque converter, and the power is output to the drive wheels via a belt-type stepless speed change mechanism provided in parallel between the input rotating member and the output rotating member that outputs the power to the drive wheels. The power of the driving force source is transmitted to the driving wheel side via a first power transmission path for transmitting the power from the driving force source to the driving wheel side and a gear type transmission mechanism in which one or a plurality of gear stages are formed. The clutch mechanism includes a second power transmission path for transmitting to the power transmission path, a clutch mechanism for selectively switching between the first power transmission path and the second power transmission path, and the first power transmission path is selected for the clutch mechanism. The first clutch and the second power transmission path, which are engaged with each other and are arranged on the output side member of the belt type stepless speed change mechanism or on the downstream side in the torque transmission path from the output side member, are selected. A control device for a vehicle power transmission, including a second clutch that is engaged when
When the input torque to the belt-type stepless speed change mechanism when gripping the first clutch and the second clutch is upshifting due to gripping from the second clutch to the first clutch, The first calculated value obtained by dividing the torque capacity of the first clutch by the gear ratio of the belt-type stepless speed change mechanism and the lower limit guard value obtained by dividing the drag torque of the first clutch by the gear ratio of the belt-type stepless speed change mechanism. When the larger value of the above is set and the downshift is in progress due to the gripping from the first clutch to the second clutch, the first calculated value and the turbine output from the torque converter turbine are in progress. Set the smaller value of the torque and
A control device for a power transmission device for a vehicle, which controls a narrow belt pressure of the belt-type continuously variable transmission mechanism based on the input torque.

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