JP2019124231A - Control device of power transmission device - Google Patents

Abstract

To provide a control device of a power transmission device which can suppress the generation of a belt slide.SOLUTION: In a control device of a power transmission device having a hydraulic control circuit having, as a power transmission path for transmitting power from a power source to drive wheels, a first path in which a belt-type continuously variable transmission including a primary pulley and a secondary pulley is arranged, and a second path which is formed parallel with the first path, and in which a gear row at which gears are engaged with one another is arranged, and supplying hydraulic pressure to a plurality of actuators, clutch-to-clutch control which is finished by gradually boosting the hydraulic pressure supplied to the hydraulic actuators up to a first target value from a start of the control is finished by quickly boosting the hydraulic pressure up to the first target value when the control exceeds a first prescribed time, and belt grip pressure boost control which is finished by gradually boosting the hydraulic pressure supplied to the hydraulic actuators up to a second target value from a start of the control quickly boosts the hydraulic pressure up to the second target value when the control exceeds a second prescribed time which is shorter than the first prescribed time, and is finished.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a control device of a power transmission device.

  According to Patent Document 1, in a control device of a power transmission device, when a shift operation is performed, a belt is provided based on input torque before engaging a clutch provided between the continuously variable transmission and the drive wheels. It is disclosed to control the belt clamping pressure of the continuously variable transmission so as not to cause slippage.

JP, 2017-82956, A

  If the clutch engagement control time is extended due to hydraulic pressure abnormality or a decrease in the friction coefficient due to aging of the friction material, etc., it is considered that the clutch oil pressure is increased to force engagement in order to prevent damage accumulation on the friction material Be At that time, in order to prevent belt slippage, it is necessary to raise the belt clamping pressure at the same timing, but the clutch oil pressure is directly controlled by the linear solenoid, and the belt clamping pressure is controlled via a valve. If the responsiveness of the clamping pressure control is poor, belt slippage may occur.

  This invention is made in view of the said subject, Comprising: The objective is to provide the control apparatus of the power transmission device which can suppress generation | occurrence | production of a belt slip.

  In order to solve the problems described above and achieve the object, a control device of a power transmission device according to the present invention includes a belt including a primary pulley and a secondary pulley as a power transmission path for transmitting power from a power source to drive wheels. And a second path provided with a gear train in which gears are engaged with each other, and the first path provided with a continuously variable transmission of A second hydraulic actuator for applying a thrust to the movable pulley of the secondary pulley, and engaging or releasing the first path and the second path when switching between the first path and the second path A control device for a power transmission device, comprising a hydraulic control circuit for supplying hydraulic pressure to a third hydraulic actuator in an engagement device The clutch-to-clutch control that completes the control by gradually increasing the hydraulic pressure supplied to the third hydraulic actuator, when the first predetermined time is exceeded, makes the hydraulic pressure increase rapidly to the first target value, and completes the control. The belt clamping pressure increase control for completing the control by gradually increasing the hydraulic pressure supplied to the second hydraulic actuator to the second target value, when the second predetermined time shorter than the first predetermined time exceeds the second target, the second target The hydraulic pressure is rapidly increased to a value to complete the control.

  The control device of the power transmission device according to the present invention performs the forced clamping pressure increase completion control of the belt clamping pressure increase control from the timer until the forced shift completion control of the clutch-to-clutch control (hereinafter referred to as CtoC control) is performed. Even if the response of belt clamping control is inferior because the timer is shorter, it is possible to prevent CtoC control from being completed before belt clamping control is completed, thus suppressing the occurrence of belt slippage. The effect of being able to

FIG. 1 is a skeleton diagram showing an example of a target vehicle in the embodiment. FIG. 2 is a block diagram for explaining an essential part of a control system provided in the vehicle. FIG. 3 is a hydraulic circuit diagram schematically showing an example of the hydraulic control circuit. FIG. 4 shows an example of a timing chart of CtoC control and belt pinching pressure increase control performed by the ECU.

  Hereinafter, an embodiment of a control device of a power transmission device according to the present invention will be described. The present invention is not limited by the present embodiment.

  FIG. 1 is a skeleton diagram showing an example of a vehicle Ve targeted in the embodiment. The vehicle Ve includes an engine 1 as a power source, a power transmission device 150, and the like. The power output from the engine 1 is provided to the power transmission device 150, the torque converter 2, which is a fluid transmission device, the input shaft 3, the forward / reverse switching mechanism 4, the belt type continuously variable transmission unit 5 or the gear train 6, It is transmitted to the drive wheel 11 through the output shaft 7, the counter gear mechanism 8, the differential gear 9, and the axle 10. Further, on the downstream side of the continuously variable transmission unit 5, a second clutch C2 is provided as a clutch for separating the engine 1 from the drive wheels 11. By releasing the second clutch C 2, torque transmission is interrupted between the continuously variable transmission unit 5 and the output shaft 7, and the continuously variable transmission unit 5 is disconnected from the driving wheel 11 in addition to the engine 1.

  Specifically, the torque converter 2 is disposed between the pump impeller 2a connected to the engine 1, the turbine runner 2b disposed facing the pump impeller 2a, and between the pump impeller 2a and the turbine runner 2b. And a stator 2c. The inside of the torque converter 2 is filled with the working fluid (oil). The pump impeller 2 a rotates integrally with the crankshaft 1 a of the engine 1. The input shaft 3 is coupled to the turbine runner 2 b so as to rotate integrally. The torque converter 2 includes a lockup clutch, and in the engaged state, the pump impeller 2a and the turbine runner 2b rotate integrally, and in the opened state, the power output from the engine 1 is transmitted to the turbine runner 2b via the working fluid. Be done. The stator 2c is held by a fixed portion such as a case via a one-way clutch.

  Further, a mechanical oil pump 41 is connected to the pump impeller 2a via a transmission mechanism such as a belt mechanism. The mechanical oil pump 41 is driven by the engine 1 because it is connected to the crankshaft 1 a via the pump impeller 2 a. The mechanical oil pump 41 and the pump impeller 2a may be configured to rotate integrally.

The input shaft 3 is coupled to the forward / reverse switching mechanism 4. The forward / reverse switching mechanism 4 switches the direction of the torque acting on the drive wheel 11 between the forward direction and the reverse direction when transmitting the engine torque to the drive wheel 11. The forward / reverse switching mechanism 4 is composed of a differential mechanism, and in the example shown in FIG. 1, is composed of a double pinion type planetary gear mechanism. Its forward-reverse switching mechanism 4, meshes with the sun gear 4S, a ring gear 4R, which is arranged concentrically with the sun gear 4S, a first pinion gear 4P ₁ meshed with the sun gear 4S, a first pinion gear 4P ₁ and gear 4R and a second pinion gear 4P ₂ has, and a carrier 4C that capable of rotating and revolve holds the first pinion gear 4P ₁ and the second pinion gear 4P _2. The drive gear 61 of the gear train 6 is connected to the sun gear 4S so as to rotate integrally. The input shaft 3 is coupled to the carrier 4C so as to rotate integrally. Further, a first clutch C1 is provided which selectively and integrally rotates the sun gear 4S and the carrier 4C. By engaging the first clutch C1, the whole forward and reverse switching mechanism 4 rotates integrally. Further, a brake B1 is provided to selectively fix the ring gear 4R in a non-rotatable manner. The first clutch C1 and the brake B1 are hydraulic.

  For example, when the first clutch C1 is engaged and the brake B1 is released, the sun gear 4S and the carrier 4C rotate integrally. That is, the input shaft 3 and the drive gear 61 integrally rotate. Further, when the first clutch C1 is released and the brake B1 is engaged, the sun gear 4S and the carrier 4C rotate in the opposite direction. That is, the input shaft 3 and the drive gear 61 rotate in the opposite direction.

  In the vehicle Ve, the continuously variable transmission unit 5 and a gear train 6 which is a stepped transmission unit are provided in parallel. As a power transmission path between the input shaft 3 and the output shaft 7, a power transmission path (hereinafter referred to as “first path”) via the continuously variable transmission unit 5 and a power transmission path (hereinafter referred to as “second "Paths" are formed in parallel.

The continuously variable transmission unit 5 includes a primary pulley 51 integrally rotating with the input shaft 3, a secondary pulley 52 integrally rotating with the secondary shaft 54, and a belt wound around V grooves formed in the primary pulley 51 and the secondary pulley 52. It has 53 and. The input shaft 3 is a primary shaft. Since the winding diameter of the belt 53 is changed by changing the V groove width of the primary pulley 51 and the secondary pulley 52, the transmission ratio γ of the continuously variable transmission unit 5 can be changed continuously. The gear ratio γ of the continuously variable transmission unit 5 continuously changes in the range from the maximum gear ratio γ _max (Low) to the minimum gear ratio γ _min (High).

The primary pulley 51 includes a fixed pulley 51a integrated with the input shaft 3, a movable pulley 51b movable in the axial direction on the input shaft 3, and a primary hydraulic actuator 51c for applying a thrust to the movable pulley 51b. There is. The pulley surface of the fixed pulley 51a and the pulley surface of the movable pulley 51b face each other to form a V groove of the primary pulley 51. The primary hydraulic actuator 51c is disposed on the back side of the movable pulley 51b. By a hydraulic (hereinafter referred to as "primary pressure") P _in supplied to the primary hydraulic actuator 51c, thrust for moving the movable pulley 51b toward the fixed pulley 51a side (primary thrust force) is generated. The primary thrust is a pressing force obtained by multiplying the pressure receiving area on the primary pressure P _in.

The secondary pulley 52 includes a fixed pulley 52a integrated with the secondary shaft 54, a movable pulley 52b axially movable on the secondary shaft 54, and a secondary hydraulic actuator 52c for applying a thrust to the movable pulley 52b. There is. The pulley surface of the fixed pulley 52a and the pulley surface of the movable pulley 52b face each other to form a V groove of the secondary pulley 52. The secondary hydraulic actuator 52c is disposed on the back side of the movable pulley 52b. By a hydraulic (hereinafter referred to as "secondary pressure") P _out is supplied to the secondary hydraulic actuator 52c, thrust for moving the movable pulley 52b toward the fixed pulley 52a side (secondary thrust) is generated. The secondary thrust is a pressing force obtained by multiplying the secondary pressure P _out by the pressure receiving area.

  The second clutch C2 is provided between the secondary shaft 54 and the output shaft 7, and can selectively disconnect the continuously variable transmission unit 5 from the output shaft 7. For example, when the second clutch C2 is engaged, power can be transmitted between the continuously variable transmission unit 5 and the output shaft 7, and the secondary shaft 54 and the output shaft 7 integrally rotate. When the second clutch C2 is released, torque transmission is interrupted between the secondary shaft 54 and the output shaft 7, and the engine 1 and the continuously variable transmission unit 5 are disconnected from the drive wheel 11. The second clutch C2 is hydraulic. The engagement elements of the second clutch C2 are frictionally engaged by the hydraulic actuator.

  The output gear 7a and the driven gear 63 are attached to the output shaft 7 so as to rotate integrally. The output gear 7a meshes with the counter driven gear 8a of the counter gear mechanism 8 which is a reduction mechanism. The counter drive gear 8 b of the counter gear mechanism 8 meshes with the ring gear 9 a of the differential gear 9. The left and right drive wheels 11 are connected to the differential gear 9 via the left and right axles 10.

The gear train 6 includes a drive gear 61 integrally rotating with the sun gear 4S of the forward / reverse switching mechanism 4, a counter gear mechanism 62, and a driven gear 63 integrally rotating with the output shaft 7. The gear train 6 is a reduction mechanism, and the transmission gear ratio (gear ratio) of the gear train 6 is set to a predetermined value larger than the maximum transmission gear ratio γ _max of the continuously variable transmission unit 5. The gear ratio of the gear train 6 is a fixed gear ratio. In the vehicle Ve, the torque is transmitted from the engine 1 to the drive wheels 11 via the gear train 6 at the time of start. The gear train 6 functions as a start gear.

  The drive gear 61 meshes with the counter driven gear 62 a of the counter gear mechanism 62. Counter gear mechanism 62 includes counter driven gear 62 a, counter shaft 62 b, and counter drive gear 62 c meshing with driven gear 63. The counter driven gear 62a is attached to the counter shaft 62b so as to rotate integrally. The counter shaft 62 b is disposed in parallel with the input shaft 3 and the output shaft 7. The counter drive gear 62c is configured to be rotatable relative to the counter shaft 62b. Further, a meshing type engagement device (hereinafter referred to as a dog clutch) S1 is provided which selectively integrally rotates the counter shaft 62b and the counter drive gear 62c.

  The dog clutch S1 includes a pair of meshing first and second engagement elements 64a and 64b, and a sleeve 64c movable in the axial direction. The first engagement element 64a is a hub spline-fitted to the countershaft 62b. The first engagement element 64a and the countershaft 62b rotate integrally. The second engagement element 64b is coupled to rotate integrally with the counter drive gear 62c. That is, the second engagement element 64b rotates relative to the countershaft 62b. When the spline teeth formed on the inner peripheral surface of the sleeve 64c mesh with the spline teeth formed on the outer peripheral surface of the first engagement element 64a and the second engagement element 64b, the dog clutch S1 is engaged. By engaging the dog clutch S1, a torque can be transmitted between the drive gear 61 and the driven gear 63 (second path). By releasing the engagement between the second engagement element 64b and the sleeve 64c, the dog clutch S1 is released. By releasing the dog clutch S1, torque transmission is interrupted between the drive gear 61 and the driven gear 63 (second path). Further, the dog clutch S1 is hydraulic, and the sleeve 64c moves in the axial direction by the hydraulic actuator. Furthermore, the dog clutch S1 is configured to include a known synchromesh mechanism.

  FIG. 2 is a block diagram for explaining an essential part of a control system provided in the vehicle Ve. The vehicle Ve according to the present embodiment is provided with an electronic control unit (hereinafter referred to as "ECU") 100 that controls the engine 1, the power transmission device 150, and the like. The ECU 100 is mainly composed of a microcomputer, performs calculation using input data and data stored in advance, and outputs the calculation result as a command signal. For example, the ECU 100 outputs a command signal to the engine 1 to control the fuel supply amount, the intake air amount, the fuel injection, the ignition timing, and the like. Further, the ECU 100 outputs an oil pressure command signal to the oil pressure control circuit 200 to maintain the transmission ratio of the continuously variable transmission unit 5, the transmission operation of the continuously variable transmission unit 5, and respective engagement devices such as the first clutch C1. Control the operation of The hydraulic control circuit 200 supplies hydraulic pressure to the hydraulic actuators 51c and 52c of the continuously variable transmission unit 5 and the hydraulic actuators of the engagement devices C1, C2, B1 and S1. The ECU 100 controls the hydraulic control circuit 200 to control switching of the power transmission path between the first path and the second path, control for maintaining the transmission ratio of the continuously variable transmission unit 5, and control of the continuously variable transmission unit 5. It performs shift control, control to switch to various travel modes, and the like.

As shown in FIG. 2, signals from various sensors 31 to 36 are input to the ECU 100. Engine speed sensor 31 detects the rotational speed of the crankshaft 1a (engine speed) N _e. The input shaft rotation speed sensor 32 detects the rotation speed (input shaft rotation speed) N _in of the input shaft 3. The output shaft rotational speed sensor 33 detects the rotational speed (output shaft rotational speed) N _out of the output shaft 7. The vehicle speed sensor 34 detects the vehicle speed V. The shift position sensor 35 detects the position of a shift lever (not shown). The hydraulic pressure sensor 36 detects a secondary pressure P _out supplied to the secondary hydraulic actuator 52 c. The ECU 100 receives signals from an accelerator opening degree sensor that detects an operation amount of an accelerator pedal and a brake stroke sensor that detects an operation amount of a brake pedal (all not shown). Further, the ECU 100 calculates the gear ratio γ (= N _in / N _out ) of the continuously variable transmission unit 5 by dividing the input shaft rotation speed N _in by the output shaft rotation speed N _out while the continuously variable transmission unit 5 is rotating. it can.

  The ECU 100 includes a traveling control unit 101 and a switching control unit 102. The traveling control unit 101 controls the vehicle Ve in a plurality of traveling modes. The switching control unit 102 performs control such that the transmission ratio of the continuously variable transmission unit 5 is maintained when switching the switching valve 206 provided in the hydraulic control circuit 200 described later using the control hydraulic pressure.

  The travel modes include three travel modes: start (gear travel), medium speed (belt travel), and high speed (belt travel). At the time of start, the first clutch C1 and the dog clutch S1 are engaged, and the second clutch C2 and the brake B1 are released. The power transmission path at the time of start is set to a second path via the gear train 6. When the vehicle speed V rises to a certain extent after the start, the traveling mode changes from the start to the middle speed by performing the grip change control in which the first clutch C1 is released and the second clutch C2 is engaged. At the medium speed, the second clutch C2 and the dog clutch S1 are engaged, and the first clutch C1 and the brake B1 are released. The power transmission path at medium speed is set to a first path via the continuously variable transmission unit 5. That is, at the time of transition from start to medium speed, the power transmission path is switched from the second path to the first path. Further, the regripping control between the first clutch C1 and the second clutch C2 is CtoC control in which the transfer torque capacity is gradually changed. When the vehicle speed V further increases while traveling at medium speed, the dog clutch S1 is released, and the traveling mode shifts from medium speed to high speed. At high speed, the second clutch C2 is engaged, and the first clutch C1, the brake B1 and the dog clutch S1 are released. At the transition from medium speed to high speed, no path switching is performed, and the power transmission path remains the first path.

  During reverse (R), the power transmission path is set to the second path via the gear train 6 by engaging the brake B1 with the dog clutch S1 and releasing the first clutch C1 and the second clutch C2. Be done. When the shift position is "N" or "P", the dog clutch S1 is engaged, and the first clutch C1, the second clutch C2 and the brake B1 are released.

  FIG. 3 is a hydraulic circuit diagram schematically showing an example of the hydraulic control circuit 200. As shown in FIG. The hydraulic control circuit 200 includes a mechanical oil pump 41 driven by the engine 1 as a hydraulic pressure supply source. The mechanical oil pump 41 sucks the oil stored in the oil pan and feeds it to the first oil passage 201. When the engine speed is high, the discharge amount of the mechanical oil pump 41 increases, and when the engine speed is low, the discharge amount of the mechanical oil pump 41 decreases.

The hydraulic control circuit 200 includes a first pressure regulating valve (primary regulator valve) 211 the oil pressure of the first oil path 201 which applies the first line pressure _{P L1} two tone, the discharged oil from the first pressure regulating valve 211 and the second line pressure a second pressure regulating valve (secondary regulator valve) 212 for pressurizing P _L2 two tone, first pressure reducing valve pressure regulating a predetermined modulator pressure _{P M} the first line pressure _{P L1} as source pressure and (modulator valve) 213, the first line second pressure reducing valve for pressurizing regulating the primary pressure _{P in} the pressure _{P L1} as a source pressure (speed ratio control valve) 214, a third reducing valve pressure regulating the secondary pressure _{P out} of the first line pressure _{P L1} as a source pressure (nip Pressure control valve) 215. The third pressure reducing valve 215 is a secondary pressure control valve for outputting a secondary pressure _{P out.} The first pressure regulating valve 211 is controlled based on a control hydraulic pressure (P _SLT ) output from a linear solenoid (SLT) not shown so as to generate a first line pressure P _L1 according to the traveling state. The second line pressure P _L2 two pressure-regulated oil by the second pressure regulating valve 212 is supplied to the torque converter 2. The oil discharged from the second pressure regulating valve 212 is supplied to a lubricating system such as a meshing portion between gears.

  A plurality of linear solenoids SL 1, SL 2, SLG, SLP, SLS are connected to the first pressure reducing valve 213 via the third oil passage 203. The linear solenoids SL 1, SL 2, SLG, SLP, SLS are controlled independently of each other by the ECU 100 to be excited, de-excited, or current controlled, and adjust hydraulic pressure according to a hydraulic pressure command signal (instruction pressure) output from the ECU 100.

Linear solenoid SL1 is a pressure regulating first clutch pressure _{P C1} to the modulator pressure _{P M} in the source pressure is supplied to the first clutch C1. Linear solenoid SL2 is a second clutch pressure _{P C2} by regulating to a modulator pressure _{P M} in the source pressure is supplied to the second clutch C2. Linear solenoid SLG is a pressure regulating modulator pressure _{P M} or the supply pressure _{P SLG} in the source pressure reverse pressure _{P R,} supplied to the dog clutch S1 and the brake B1. The linear solenoid SLG, includes an input port modulator pressure P _M is input, an input port reverse pressure P _R is input. By ECU100 based on the operation of the shift lever (not shown) to control the linear solenoid SLG, source pressure of the feed pressure _{P SLG} is switched to the modulator pressure _{P M} or reverse pressure _{P R.} The output port of the linear solenoid SLG is connected to the dog clutch S1 and the brake B1 via the switching valve 206.

The switching valve 206 is an S1-B1 apply control valve (S1-B1ACV), and switches the supply destination of the supplied hydraulic pressure P _SLG to the dog clutch S1 and the brake B1 according to the control hydraulic pressure P _SLS input from the linear solenoid SLS. To work. Moreover, modulator pressure P _M from the another port is input to the switching valve 206 and port supply pressure P _SLG are inputted. By ECU100 to switch control the switching valve 206 based on the operation of the shift lever, it may be supplied to the modulator pressure _{P M} in the dog clutch S1 via the switching valve 206.

Specifically, when the shift lever is in the "D" position, the supply pressure P _SLG that the modulator pressure P _M in the source pressure is supplied to the dog clutch S1. If the shift lever is in the "R" position, the supply pressure P _SLG you source pressure reverse pressure P _R is supplied to the brake B1 via the switching valve 206, and the dog clutch S1 modulator pressure P _M via the switching valve 206 Supplied to When the control oil pressure P _SLS equal to or greater than a predetermined value is output at the “R” position, the switching valve 206 to which the control oil pressure P _SLS is input can be switched from the brake B1 side to the dog clutch S1 side. Thus, the switching valve 206 functions as a valve that switches the supply destination of the supplied hydraulic pressure _PSLG . The hydraulic control circuit 200 includes a manual valve (not shown) that mechanically operates in response to the operation of the shift lever. When the shift lever is in the "R" position, since the reverse pressure P _R occurs, the reverse pressure P _R via the manual valve is supplied to the linear solenoid SLG.

Linear solenoid SLP is by regulating the control oil pressure _{P SLP} as source pressure modulator pressure _{P M,} and outputs it to the second pressure reducing valve 214. The linear solenoid SLP is a primary solenoid valve. Linear solenoid SLS is by regulating the control oil pressure _{P SLS} as source pressure modulator pressure _{P M,} and outputs it to the third pressure reducing valve 215. The linear solenoid SLS is a secondary solenoid valve. Further, in the hydraulic control circuit 200, the control hydraulic pressure P _SLS output from the linear solenoid SLS is input to the switching valve 206.

The primary hydraulic actuator 51 c is connected to the second pressure reducing valve 214 via the fourth oil passage 204. The second pressure reducing valve 214 and the fourth oil passage 204 form a transmission ratio control circuit of the continuously variable transmission unit 5. The second pressure reducing valve 214 is a valve for controlling the gear ratio γ of the continuously variable transmission unit 5. The second pressure reducing valve 214 controls the amount of oil (hydraulic pressure) supplied to the primary hydraulic actuator 51 c. Second pressure reducing valve 214, the primary pressure _{P in} by regulating the first line pressure _{P L1} as an original pressure supplied to the primary hydraulic actuator 51c. Second pressure reducing valve 214 pressure regulates the primary pressure _{P in} the basis of the control oil pressure _{P SLP} inputted from the linear solenoid SLP. ECU100 regulates the primary pressure _{P in} by controlling the hydraulic pressure command signal to be output to the linear solenoid SLP. V groove width of the primary pulley 51 is changed by the primary pressure P _in is changed. ECU100 controls the γ gear ratio of the continuously variable transmission 5 by controlling the primary pressure _{P in.}

A secondary hydraulic actuator 52 c is connected to the third pressure reducing valve 215 via the fifth oil passage 205. The third pressure reducing valve 215 and the fifth oil passage 205 form a clamping pressure control circuit of the continuously variable transmission unit 5. The third pressure reducing valve 215 is a valve that controls the belt clamping pressure. The third pressure reducing valve 215 controls the amount of oil (hydraulic pressure) supplied to the secondary hydraulic actuator 52c. The third pressure reducing valve 215, the secondary pressure _{P out} by regulating the first line pressure _{P L1} as an original pressure supplied to the secondary hydraulic actuator 52c. The third pressure reducing valve 215 regulates the secondary pressure P _out based on the control oil pressure P _SLS input from the linear solenoid SLS. The ECU 100 adjusts the secondary pressure P _out by controlling the hydraulic pressure command signal output to the linear solenoid SLS. As the secondary pressure P _out changes, the belt clamping pressure of the continuously variable transmission unit 5 changes. ECU100 controls the clamping pressure of the continuously variable transmission 5 by controlling the secondary pressure _{P out.}

The belt clamping pressure is a force for clamping the belt 53 by the V grooves of the primary pulley 51 and the secondary pulley 52. The belt clamping pressure generates a frictional force between primary pulley 51 and secondary pulley 52 and belt 53 at rotating continuously variable transmission unit 5, and is wound around V-grooves of primary pulley 51 and secondary pulley 52. The belt 53 is tensioned. The ECU 100 regulates and controls the secondary pressure P _out by the linear solenoid SLS and the third pressure reducing valve 215 so that the necessary belt clamping pressure is generated. For example, when the control oil pressure _PSLS input to the third pressure reducing valve 215 becomes high, the third pressure reducing valve 215 operates to increase the secondary pressure P _out . In this case, the ECU 100 can increase the hydraulic pressure command value output to the linear solenoid SLS to increase the belt clamping pressure.

  Here, the shift time of the CtoC control may be prolonged due to an unintended hydraulic pressure abnormality or a decrease in the friction coefficient due to the aging of the friction material. If the condition continues for a long time, the heat generation amount of the friction material may increase, which may lead to further damage to the friction material. Therefore, shift to forced shift termination (forced engagement due to increase in clutch hydraulic pressure) is performed at a certain shift time (timer). At that time, the belt clamping pressure is also increased for belt slip protection, but there is a concern that the clutch torque capacity sometimes exceeds the belt torque capacity due to the difference in responsiveness between the clutch pressure and the belt clamping pressure. . This is because, for example, while the linear solenoid controlling the clutch pressure directly controls the clutch pressure, the belt clamping pressure is controlled via the valve, so in the simultaneous control, the belt clamping pressure is It is because it will be inferior as responsiveness.

FIG. 4 shows an example of a timing chart of the CtoC control and the belt clamping pressure increase control which the ECU 100 performs. In the present embodiment, as shown in FIG. 4, the ECU 100 gradually increases the hydraulic pressure (second clutch pressure) supplied to the actuator of the second clutch C2 from the start of control to the second clutch pressure target value which is the first target value. in completing CtoC control control, if it exceeds the first timer T ₁ is a first predetermined time, to complete the control by rapidly increasing the oil pressure (second clutch pressure) to the second clutch pressure target value. Further, as shown in FIG. 4, the ECU 100 gradually increases the hydraulic pressure (belt clamping pressure) supplied to the secondary hydraulic actuator 52c from the control start to the second target value, the belt clamping target value, and completes the control. in pressure increase control, if it exceeds the second timer T ₂ is a first second predetermined time shorter than the timer T _1, to complete the control by rapidly increasing the oil pressure (belt clamping pressure) to the belt clamping pressure target value.

Thus, in the present embodiment, from the first timer T ₁ of the until the force transmission completion control of CtoC control, the belt clamping pressure increasing control force pinching up performing rise completion control of the second timer T ₂ Even if the responsiveness of the belt clamping control is inferior, the CtoC control can be prevented from completing before the belt clamping control is completed, and belt slippage can be suppressed even if the responsiveness of the belt clamping control is inferior.

1 engine 5 continuously variable transmission unit 6 gear train 11 drive wheel 51 primary pulley 51b movable pulley 51c primary hydraulic actuator 52 secondary pulley 52b movable pulley 52c secondary hydraulic actuator 100 ECU
150 power transmission device 200 hydraulic control circuit C2 second clutch

Claims (1)

A first path provided with a belt-type continuously variable transmission including a primary pulley and a secondary pulley as a power transmission path for transmitting power from a power source to the drive wheels, and the first path are formed in parallel, And a second path provided with a gear train in which the gears mesh with each other,
A first hydraulic actuator applying thrust to the movable pulley of the primary pulley, a second hydraulic actuator applying thrust to the movable pulley of the secondary pulley, and engagement when switching between the first path and the second path Alternatively, in a control device for a power transmission device, the control device for a power transmission device includes a hydraulic control circuit that supplies hydraulic pressure to a third hydraulic actuator in an engagement device that opens.
The clutch-to-clutch control which completes the control by gradually increasing the hydraulic pressure supplied to the third hydraulic actuator from the start of control to the first target value, rapidly increases the hydraulic pressure to the first target value when the first predetermined time is exceeded. Complete control and
The belt clamping pressure increase control for completing the control by gradually increasing the hydraulic pressure supplied to the second hydraulic actuator from the start of control to the second target value, when the second predetermined time shorter than the first predetermined time is exceeded, A control device for a power transmission device, wherein the control is completed by rapidly increasing the hydraulic pressure to a second target value.

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