JP2015135122A - Vehicle control device, and vehicle control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle control device having a continuously variable transmission which is enhanced in shift speed.SOLUTION: A vehicle control device for controlling a vehicle comprises a continuously variable transmission 1 having a primary pulley 2 having a second oil chamber 2d and a first oil chamber 2c communicating with a third oil chamber 3c of a secondary pulley 3. The vehicle control device also comprises: thrust ratio calculation means 6 which calculates a thrust ratio being a value which is obtained by dividing a primary thrust by a secondary thrust; instruction thrust ratio calculation means 6 which calculates an instruction thrust ratio that achieves a target speed ratio of the continuously variable transmission 1; and hydraulic pressure control means 6 which controls hydraulic pressure supply means 7 on the basis of the instruction thrust ratio. When the instruction thrust ratio is smaller than a lower limit thrust ratio which is set by dividing a pressure receiving area of the first oil chamber 2c by a pressure receiving area of the third oil chamber 3c, the hydraulic pressure control means 6 controls the hydraulic pressure supply means 7 so that a difference between the thrust ratio and the lower limit thrust ratio becomes large.

Description

  The present invention relates to a vehicle control device and a vehicle control method.

  Conventionally, Patent Document 1 discloses a continuously variable transmission in which a first oil chamber and a second oil chamber are provided as oil chambers of a primary pulley, and the first oil chamber and the oil chamber of a secondary pulley are communicated by an oil passage. Yes.

JP 2009-236255 A

  In a continuously variable transmission, when shifting to the Low side, the oil in the primary pulley oil chamber is reduced to reduce the thrust of the primary pulley, or the oil in the secondary pulley oil chamber is increased to increase the thrust of the secondary pulley. The shift can be realized by increasing or both. That is, by reducing the thrust ratio obtained by dividing the thrust of the primary pulley by the thrust of the secondary pulley, the shift to the Low side can be realized, the target thrust ratio is reduced, and the current thrust ratio and the target thrust ratio are By increasing the difference, it is possible to increase the shift speed and quickly shift to the Low side.

  However, in the above invention, when shifting the transmission ratio of the continuously variable transmission to the Low side, it is possible to make the hydraulic pressure of the second oil chamber not communicating with the oil chamber of the secondary pulley zero. Since the first oil chamber communicates with the oil chamber of the secondary pulley, when the oil pressure is supplied to the oil chamber of the secondary pulley, the oil pressure is also supplied to the first oil chamber, and the oil pressure of the first oil chamber is lowered. I can't. Therefore, after the oil pressure in the second oil chamber becomes zero, it is not possible to make the thrust ratio smaller than the lower limit thrust ratio obtained by dividing the pressure receiving area of the first oil chamber by the pressure receiving area of the oil chamber of the secondary pulley, The difference between the current thrust ratio and the target thrust ratio cannot be increased, the shift speed cannot be increased, and the shift to the Low side cannot be performed quickly.

  The present invention has been invented to solve such problems. The primary pulley has a first oil chamber and a second oil chamber, and the first oil chamber communicates with the oil chamber of the secondary pulley. An object of the continuously variable transmission is to increase the shift speed and quickly shift to the Low side.

  A vehicle control device according to an aspect of the present invention includes a first oil chamber and a second oil chamber, and a first thrust generated by the oil pressure of the first oil chamber and a second thrust generated by the oil pressure of the second oil chamber. A primary pulley that displaces the movable pulley in the axial direction of the fixed pulley in accordance with the primary thrust that is the total thrust of the second pulley, and a third oil chamber that communicates with the first oil chamber, and a secondary that is generated by the hydraulic pressure of the third oil chamber A secondary pulley that displaces the movable pulley in the axial direction of the fixed pulley according to thrust, and a hydraulic pressure supply means that supplies hydraulic pressure to the first oil chamber and the third oil chamber, and the hydraulic pressure is supplied to the third oil chamber When this is done, it is a vehicle control device for controlling a vehicle including a continuously variable transmission in which oil is supplied to the first oil chamber, and a thrust ratio that calculates a thrust ratio that is a value obtained by dividing the primary thrust by the secondary thrust. Achieving the target transmission ratio of the calculation means and continuously variable transmission An instruction thrust ratio calculating means for calculating an instruction thrust ratio; and a hydraulic control means for controlling the hydraulic pressure supply means based on the instruction thrust ratio. The oil pressure control means has an instruction thrust ratio indicating a pressure receiving area of the first oil chamber. When it is smaller than the lower limit thrust ratio set by dividing by the pressure receiving area of the third oil chamber, the hydraulic pressure supply means is controlled so that the difference between the thrust ratio and the lower limit thrust ratio becomes large.

  A vehicle control method according to another aspect of the present invention includes a first oil chamber and a second oil chamber, and a second thrust generated by the first thrust generated by the oil pressure of the first oil chamber and the oil pressure of the second oil chamber. It has a primary pulley that displaces the movable pulley in the axial direction of the fixed pulley according to the primary thrust that is the total thrust with the thrust, and a third oil chamber that communicates with the first oil chamber, and is generated by the hydraulic pressure of the third oil chamber A secondary pulley that displaces the movable pulley in the axial direction of the fixed pulley according to the secondary thrust; and a hydraulic pressure supply means that supplies hydraulic pressure to the first oil chamber and the third oil chamber. A vehicle control method for controlling a vehicle including a continuously variable transmission in which oil is supplied to a first oil chamber when hydraulic pressure is supplied to the chamber, wherein the thrust ratio is a value obtained by dividing primary thrust by secondary thrust To achieve the target gear ratio of the continuously variable transmission When the commanded thrust ratio is smaller than the lower limit thrust ratio set by dividing the pressure receiving area of the first oil chamber by the pressure received area of the third oil chamber, the thrust ratio and the lower limit thrust ratio are calculated. The hydraulic pressure supply means is controlled so as to increase the difference.

  According to these aspects, even when the command thrust ratio for achieving the target gear ratio is smaller than the acceleration / deceleration thrust ratio, the gear speed can be increased by controlling the hydraulic pressure supplied to the secondary pulley by the hydraulic pressure supply means. Shift to the side can be performed quickly.

It is a schematic block diagram of the continuously variable transmission of this embodiment. It is a flowchart which shows the shift control of this embodiment. It is a map which shows the relationship between transmission torque ratio, balance thrust ratio, and gear ratio. It is a map which shows the relationship between a request | requirement transmission speed and a transmission difference thrust. It is a time chart which shows the shift control of this embodiment.

  A continuously variable transmission according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic configuration diagram of a continuously variable transmission mounted on a vehicle.

  The continuously variable transmission 1 includes a primary pulley 2, a secondary pulley 3, a belt 4, a hydraulic control circuit 5, and a controller 6.

  The primary pulley 2 includes a fixed pulley 2a, a movable pulley 2b, a first oil chamber 2c, and a second oil chamber 2d. The primary pulley 2 forms a V-shaped groove by the fixed pulley 2a and the movable pulley 2b.

  The first oil chamber 2 c is formed on the back side of the movable pulley 2 b, and the hydraulic pressure is supplied and discharged by the hydraulic control circuit 5. The first oil chamber 2c communicates with the oil chamber 3c of the secondary pulley 3, and when hydraulic pressure is supplied to or discharged from the oil chamber 3c of the secondary pulley 3, the hydraulic pressure is supplied to or discharged from the first oil chamber 2c accordingly. Is done.

  The second oil chamber 2 d is formed closer to the movable pulley 2 b than the first oil chamber 2 c, and the hydraulic pressure is supplied and discharged via the hydraulic control circuit 5. The second oil chamber 2d does not communicate with the oil chamber 3c of the secondary pulley 3, and the hydraulic pressure supplied to and discharged from the second oil chamber 2d is independent of the hydraulic pressure supplied to and discharged from the first oil chamber 2c. Controlled.

  By controlling the hydraulic pressure of the first oil chamber 2c and the hydraulic pressure of the second oil chamber 2d, the thrust of the movable pulley 2b of the primary pulley 2 (hereinafter referred to as primary thrust) is controlled, and the movable pulley 2b Accordingly, the fixed pulley 2a is displaced in the axial direction, and the clamping force of the belt 4 in the primary pulley 2 is controlled. The primary thrust is a thrust generated by the hydraulic pressure supplied to the first oil chamber 2c (hereinafter referred to as a first thrust) and a thrust generated by the hydraulic pressure supplied to the second oil chamber 2d (hereinafter referred to as a second thrust). .) And total thrust.

  The secondary pulley 3 includes a fixed pulley 3a, a movable pulley 3b, and an oil chamber 3c. The secondary pulley 3 forms a V-shaped groove by the fixed pulley 3a and the movable pulley 3b.

  The oil chamber 3 c is formed on the back side of the movable pulley 3 b, and the hydraulic pressure is supplied and discharged by the hydraulic control circuit 5. The oil chamber 3c communicates with the first oil chamber 2c. The pressure receiving area of the oil chamber 3c is larger than the pressure receiving area of the first oil chamber 2c of the primary pulley.

  By controlling the hydraulic pressure of the oil chamber 3c, the thrust of the movable pulley 3b of the secondary pulley 3 (hereinafter referred to as secondary thrust) is controlled, and the movable pulley 3b is displaced in the axial direction of the movable pulley 3b according to the secondary thrust. And the clamping force of the belt 4 in the secondary pulley 3 is controlled.

  The belt 4 is stretched between the V groove of the primary pulley 2 and the V groove of the secondary pulley 3, and transmits power between the primary pulley 2 and the secondary pulley 3. Contact between the belt 4, the primary pulley 2, and the belt 4 and the secondary pulley 3 by supplying and discharging hydraulic pressure to and from the first oil chamber 2 c, the second oil chamber 2 d of the primary pulley 2, and the oil chamber 3 c of the secondary pulley 3. The radius is changed, and the gear ratio of the continuously variable transmission 1 is changed.

  The hydraulic control circuit 5 includes an oil pump 7, a regulator valve 8, a pressure reducing valve 9, a first primary pressure supply path 10, a second primary pressure supply path 11, and a secondary pressure supply path 12. An orifice 13 is provided in the secondary pressure supply path 12 closer to the regulator valve 8 than the first primary pressure supply path 10.

  The regulator valve 8 adjusts the hydraulic pressure discharged from the oil pump 7 to adjust the line pressure. The pressure reducing valve 9 reduces the line pressure to a predetermined hydraulic pressure that is supplied to the second oil chamber 2 d of the primary pulley 2.

  The line pressure is supplied to and discharged from the oil chamber 3 c of the secondary pulley 3 through the secondary pressure supply path 12. A part of the line pressure is supplied to and discharged from the first oil chamber 2 c through the first primary pressure supply path 10 branched from the secondary pressure supply path 12. That is, when the hydraulic pressure is supplied to the oil chamber 3 c of the secondary pulley 3 via the secondary pressure supply path 12, a part of the hydraulic pressure is the first oil chamber of the primary pulley 2 via the first primary pressure supply path 10. 2c is also supplied. Since the hydraulic pressure supplied to the oil chamber 3c of the secondary pulley 3 is supplied to the first oil chamber 2c of the primary pulley 2, the second oil chamber is used when the gear ratio of the continuously variable transmission 1 is changed to the High side. When the hydraulic pressure supplied to 2d is increased, a hydraulic pressure difference required for shifting, that is, a differential thrust between the primary thrust and the secondary thrust is generated.

  The controller 6 includes a signal related to the input torque Tin output from an engine controller (not shown), a signal output from the accelerator pedal opening sensor 20, a signal output from the primary pulley rotational speed sensor 21, and a secondary pulley rotational speed sensor 22. The output signal and the signal output from the vehicle speed sensor 23 are input. Based on these signals, the controller 6 outputs signals for controlling the regulator valve 8, the pressure reducing valve 9, and the like.

  The controller 6 is constituted by a CPU, a ROM, a RAM, and the like, and each function of the controller 6 is exhibited by reading a program stored in the ROM by the CPU.

  Next, the shift control of this embodiment will be described with reference to the flowchart of FIG. Here, a case will be described in which the vehicle is in a coasting state and shifts to the lowest level. The coast state is a state where the accelerator pedal is not depressed. In the coast state, the amount of change per unit time of the input torque Ti input from the engine to the continuously variable transmission 1 is minute and is constant in this control.

In step S100, the controller 6 calculates a secondary thrust _FZS that does not cause belt slip in the continuously variable transmission 1 based on the input torque Tin.

  In step S101, the controller 6 calculates the current balance thrust ratio (thrust ratio) F from the transmission torque ratio T and the current gear ratio based on the map of FIG. FIG. 3 is a diagram illustrating the relationship among the transmission torque ratio T, the transmission ratio, and the balance thrust ratio F. The transmission torque ratio T is a value obtained by dividing the input torque Tin by the maximum input torque TinMAX that can be transmitted by the current thrust. The transmission torque ratio T is a negative value when the vehicle is in a coast state, and is a positive value when the vehicle is in a drive state. The gear ratio is calculated by dividing the primary pulley rotational speed by the secondary pulley rotational speed. The balance thrust ratio F is a value obtained by dividing the primary thrust FP by the secondary thrust FS. The balance thrust ratio F indicates a thrust ratio based on the hydraulic pressure actually supplied to the first oil chamber 2c, the second oil chamber 2d of the primary pulley 2, and the oil chamber 3c of the secondary pulley 3.

In step S102, the controller 6 calculates a shift difference thrust from the requested shift speed based on the map of FIG. 4, and calculates a primary difference thrust F _{ZDIF_P} and a secondary difference thrust F _{ZDIF_S} for generating the shift difference thrust. The required shift speed is calculated based on the accelerator pedal depression amount, the vehicle speed, and the like. Here, the primary differential thrust _{FZDIF_P} is _set to zero, and the shift differential thrust is set to the secondary differential thrust _{FZDIF_S} . When a shift difference thrust is generated in the continuously variable transmission 1 according to the requested shift speed, the continuously variable transmission 1 executes a shift according to the target gear ratio.

In step S103, the controller 6 adds the speed difference thrust _{F ZDIF_S} the secondary thrust _{F ZS,} calculates the shift secondary thrust _{F ZS_out} required shift.

In step S104, the controller 6 calculates the primary thrust force _{F ZP} commensurate with secondary thrust _{F ZS} by multiplying the balance thrust ratio F to the secondary thrust force _{F ZS,} by adding the primary thrust difference _{F ZDIF_P} thereto, the primary thrust force F _{ZP_out} is calculated. Here, the primary differential thrust _{FZDIF_P} is zero.

In step S105, the controller 6 calculates a first thrust F _{ZP_out1} that is a thrust generated by the hydraulic pressure supplied to the first oil chamber 2c of the primary pulley 2. The first thrust F _{ZP_out1} is a value obtained by multiplying the speed change secondary thrust F _{ZS_out} by a value obtained by dividing the pressure receiving area AreaP1 of the first oil chamber 2c of the primary pulley 2 by the pressure receiving area AreaS of the oil chamber 3c of the secondary pulley 3.

In step S106, the controller 6 calculates a second thrust F _{ZP_out2} that is a thrust generated by the hydraulic pressure supplied to the second oil chamber 2d of the primary pulley 2. The second thrust F _{ZP_out2} is calculated by subtracting the first thrust F _{ZP_out1} from the primary thrust F _{ZP_out} .

The oil _pressure chamber 3c of the secondary pulley 3 and the primary pulley 2 of the primary pulley 2 are set so as to be the transmission secondary thrust F _{ZS_out} calculated in step S103, the first thrust F _{ZP_out1} calculated in step S105, and the second thrust F _{ZP_out2} calculated in step S106. When the hydraulic pressure supplied to the first oil chamber 2c and the second oil chamber 2d is controlled, the thrust ratio set to achieve the target shift speed becomes the command thrust ratio.

In step S107, the controller 6 determines whether or not the second thrust F _{ZP_out2} is equal to or less than zero. Controller 6, when the second thrust _{F ZP_out2} is less than zero, the process proceeds to step S108, if the second thrust _{F ZP_out2} is greater than zero, the process proceeds to step S112.

When the second thrust F _{ZP_out2} becomes zero or less in step S107, the movable pulley 2b of the primary pulley 2 is not pushed toward the fixed pulley 2a depending on the hydraulic pressure supplied to the second oil chamber 2d of the primary pulley 2. _Becomes equal to the first thrust F _{ZP_out1} . Since the first oil chamber 2c of the primary pulley 2 and the oil chamber 3c of the secondary pulley 3 communicate with each other, the oil pressures of the two oil chambers 2c and 3c are substantially equal. Therefore, in the operation state in which the second thrust _{FZP_out2} is less than or equal to zero, the indicated thrust ratio is fixed by the ratio of the pressure receiving area of the first oil chamber 2c of the primary pulley 2 to the oil receiving chamber 3c of the secondary pulley 3. Is done. That is, when the second thrust _{FZP_out2} becomes zero or less, the command thrust ratio becomes the lower limit thrust ratio, and the target command thrust ratio cannot be achieved. The lower limit thrust ratio is a value obtained by dividing the pressure receiving area of the first oil chamber 2c of the primary pulley 2 by the pressure receiving area of the oil chamber 3c of the secondary pulley 3, and the primary oil pressure when the oil pressure of the second oil chamber 2d becomes zero. The ratio of thrust and secondary thrust is shown.

When the second thrust F _{ZP_out2} is less than or equal to zero, it is assumed that the vehicle is in a driving state in which the vehicle decelerates and the gear ratio increases to near the lowest. For example, in the map shown in FIG. 3, when shifting from the state where the driving state of the vehicle is the point A to the lowest level, the transmission ratio T is kept constant by making the transmission torque ratio T constant and the transmission ratio is made the lowest. Can be changed. However, when the target gear ratio is temporarily instructed to a value larger than the maximum Low in order to quickly change the gear ratio to the lowest level, the indicated thrust ratio is smaller than the lower limit thrust ratio (in FIG. 3, Even if the hydraulic pressure is controlled so as to be (B point), the indicated thrust ratio cannot actually be made smaller than the lower limit thrust ratio. In FIG. 3, as the length of the arrow (the difference between the balance thrust ratio according to the current gear ratio and the balance thrust ratio according to the target gear ratio) is longer, the speed can be increased and the speed ratio is maximized. It shows that it can be changed quickly to Low. Thus, since the command thrust ratio cannot be made smaller than the lower limit thrust ratio, the shift speed cannot be increased, and the shift ratio cannot be quickly changed to the lowest level.

  Therefore, in the present embodiment, the transmission torque ratio T is changed in order to quickly change the gear ratio to the lowest level. The transmission torque ratio T is a value obtained by dividing the input torque Tin by the maximum input torque TinMAX that can be transmitted by the current thrust. In the present embodiment, the transmission torque ratio T is changed by increasing the maximum input torque TinMAX. The maximum input torque TinMAX is changed by changing the belt clamping force in the secondary pulley 3, that is, the secondary thrust. As a result, the operating state of the continuously variable transmission 1 is changed to a state at point C in FIG. 3, and the length of the arrow becomes longer than before the change, and the instruction thrust ratio and the lower limit thrust ratio are reduced. The difference increases. Therefore, the transmission speed can be increased, and the transmission ratio can be quickly changed to the lowest level.

In step S108, the controller 6 calculates a new secondary thrust _{FZS_outN} based on the equation (1).

  Expression (1) is a modification of Expression (2).

  Expression (2) is obtained by modifying Expression (3) as follows.

The characteristics of the shift differential thrust when shifting in a state where the second thrust F _{ZP_out2} due to the hydraulic pressure supplied to the second oil chamber 2d of the primary pulley 2 is zero or less is the secondary thrust F _{ZS in} which belt slip does not occur. The deviation between the balance thrust ratio F and the area ratio (AreaP1 / AreaS) between the pressure receiving area AreaP1 of the first oil chamber 2c of the primary pulley 2 and the pressure receiving area AreaS of the oil chamber 3c of the secondary pulley 3 and the new secondary thrust F It was found that it is proportional to _{ZS_outN} . Equation (2) shows this relationship. Here, F _{ZDIF_P in} equation (2) is zero, F _{ZDIF_ALL} is a shift difference thrust required for shifting, and the second thrust F _{ZP_out2} is a secondary difference thrust (−F _{ZDIF_S} ).

In step S109, the controller 6 _compares the new secondary thrust _{FZS_outN} with the secondary strength limit thrust. The controller 6, when the new secondary thrust _{F ZS_outN} is below secondary strength limit thrust proceeds to step S110, in case the new secondary thrust _{F ZS_outN} is greater than the secondary intensity limit thrust proceeds to step S111. The secondary strength limit thrust is a value set in advance and is an upper limit thrust at which the continuously variable transmission 1 does not deteriorate.

In step S110, the controller 6 controls the hydraulic pressure so that the secondary thrust becomes the new secondary thrust _{FZS_outN} . Specifically, the controller 6 controls the regulator valve 8. As a result, the maximum input torque TinMAX increases, the transmission torque ratio T increases, and the difference between the commanded thrust ratio and the lower limit thrust ratio increases, so that shifting to the lowest level can be performed quickly.

  In step S111, the controller 6 controls the hydraulic pressure so that the secondary thrust becomes the secondary strength limit thrust. Specifically, the controller 6 controls the regulator valve 8. Thereby, it is possible to quickly shift to the lowest level while suppressing deterioration of the continuously variable transmission 1.

In Step S112, the controller 6 controls the hydraulic pressure so that the secondary thrust becomes the shift secondary thrust F _{ZS_out} and the second thrust becomes the second thrust F _{ZP_out2} calculated in Step S106. Specifically, the controller 6 controls the regulator valve 8 and the pressure reducing valve 9.

  Next, the shift control of this embodiment will be described with reference to the time chart of FIG.

  At time t0, the vehicle decelerates and a shift is started to change the gear ratio of the continuously variable transmission 1 to the lowest level. In order to shift to the Low side, hydraulic pressure is supplied to the oil chamber 3c of the secondary pulley 3, the secondary pulley pressure increases, and the secondary thrust increases (A in FIG. 5). Since the first oil chamber 2c of the primary pulley 2 communicates with the oil chamber 3c of the secondary pulley 3, when the oil pressure is supplied to the oil chamber 3c of the secondary pulley 3, the oil pressure is also supplied to the first oil chamber 2c. The first thrust of the pulley 2 increases (B in FIG. 5). Since the primary thrust is reduced in order to change the gear ratio to the lowest level, the primary pulley 2 takes into account the increase in the first thrust, and the hydraulic pressure is discharged from the second oil chamber 2d of the primary pulley 2, and the second thrust is (C in FIG. 5).

  When the second thrust becomes zero or less at time t1, the differential thrust for the second thrust is supplied to the oil chamber 3c of the secondary pulley 3 so as to be generated as a differential thrust between the secondary thrust and the first thrust. The hydraulic pressure is increased and the secondary thrust is increased (D in FIG. 5). As a result, the maximum input torque is increased and the transmission torque ratio is increased, so that the transmission speed can be increased and the transmission ratio can be quickly changed to the lowest level. In FIG. 5, the shortage of the second thrust is indicated by a broken line (E in FIG. 5). When the hydraulic pressure supplied to the oil chamber 3c of the secondary pulley 3 is increased, the hydraulic pressure supplied to the first oil chamber 2c of the primary pulley 2 is also increased, but the pressure receiving area of the oil chamber 3c of the secondary pulley 3 is the same as that of the primary pulley 2. Since it is larger than the pressure receiving area of one oil chamber 2c, the differential thrust between the secondary thrust and the first thrust (primary thrust) increases. Therefore, the speed change speed can be increased and the speed ratio can be quickly changed to the lowest level.

  At time t2, when the speed ratio is at the lowest level and the vehicle stops, the speed ratio is maintained at the lowest level. The secondary thrust and the first thrust decrease so as to be a predetermined thrust that does not cause belt slip. In preparation for the next start, the hydraulic pressure is supplied to the second oil chamber 2d of the primary pulley 2 and the second thrust is increased.

  In FIG. 5, the secondary strength limit thrust is indicated by a one-dot chain line. When the secondary thrust becomes the secondary strength limit thrust, the secondary thrust is maintained at the secondary strength limit thrust.

  The effect of the embodiment of the present invention will be described.

  The primary pulley 2 has a first oil chamber 2c communicating with the oil chamber 3c of the secondary pulley 3, and a second oil chamber 2d not communicating with the oil chamber 3c of the secondary pulley 3, and an instruction for achieving the target gear ratio When the thrust ratio is smaller than the lower limit thrust ratio, the transmission torque ratio is changed so that the difference between the current indicated thrust ratio and the lower limit thrust ratio becomes large. As a result, the shift speed increases, and the shift to the Low side can be performed quickly (effect corresponding to claim 1).

  A continuously variable transmission having one primary pulley oil chamber and one secondary pulley oil chamber is generally used, but in order to reduce the hydraulic pressure required for shifting, two oils are respectively provided for the primary pulley and the secondary pulley. It is also possible to provide a chamber. In this continuously variable transmission, the first oil chamber of the primary pulley and the first oil chamber of the secondary pulley, and the second oil chamber of the primary pulley and the second oil chamber of the secondary pulley are communicated. In this continuously variable transmission, the hydraulic pressure required for shifting can be reduced, but since shifting is achieved by the oil traveling in each oil chamber, the oil supplied to the oil chamber is generated in order to generate thrust necessary for shifting. There is a problem that the amount increases.

  Therefore, in order to suppress an increase in the amount of oil supplied to the oil chamber while lowering the hydraulic pressure required for shifting, the first oil chamber of the primary pulley and the oil chamber of the secondary pulley are communicated with each other, and the second oil of the primary pulley is communicated. It is conceivable to provide a continuously variable transmission that does not allow the chamber to communicate with the oil chamber of the secondary pulley. In the present embodiment, in such a continuously variable transmission, shifting to the Low side can be performed quickly.

  In the present embodiment, when the hydraulic pressure is supplied to the oil chamber 3c of the secondary pulley 3 in order to change the gear ratio to the Low side, the hydraulic pressure is also supplied to the first oil chamber 2c of the primary pulley 2. Therefore, when the second thrust due to the hydraulic pressure of the second oil chamber 2d of the primary pulley 2 becomes zero or less, the indicated thrust ratio becomes the pressure receiving area of the first oil chamber 2c of the primary pulley 2 as the pressure receiving area of the oil chamber 3c of the secondary pulley 3. Fixed to the lower limit thrust ratio divided by. In such a continuously variable transmission 1 as well, by changing the transmission torque ratio, it is possible to increase the shift speed and quickly shift to the Low side.

When the second thrust F _{ZP_out2} is equal to or less than zero, the differential thrust for the second thrust F _{ZP_out2} that is insufficient is supplied to the oil chamber 3c of the secondary pulley 3 and the first oil chamber 2c of the primary pulley 2. Increase hydraulic pressure. As a result, the shift to the Low side can be performed quickly, and the amount of increase in hydraulic pressure in the oil chamber 3c of the secondary pulley 3 and the first oil chamber 2c of the primary pulley 2 can be reduced. Therefore, the shift to the Low side can be performed quickly and the driving force consumption in the oil pump 7 can be suppressed (effect corresponding to claims 2 and 5).

  When the vehicle is in a coast state and the commanded thrust ratio is smaller than the lower limit thrust ratio, the hydraulic pressure supplied to the oil chamber 3c of the secondary pulley 3 and the first oil chamber 2c of the primary pulley 2 is increased to change the speed. The speed can be increased and the shift to the Low side can be performed quickly (effect corresponding to claim 3).

  It goes without saying that the present invention is not limited to the above-described embodiments, and includes various modifications and improvements that can be made within the scope of the technical idea.

  In this embodiment, increasing the transmission torque ratio T increases the balance thrust ratio F, thereby increasing the difference between the indicated thrust ratio and the lower limit thrust ratio, and increasing the shift speed to quickly shift to the Low side. However, the difference between the indicated thrust ratio and the lower limit thrust ratio may be increased by reducing the transmission torque ratio T. Also by this, the shift speed can be increased and the shift to the Low side can be performed quickly.

  In the present embodiment, the hydraulic pressure is supplied to the oil chamber 3c of the secondary pulley 3 and the first oil chamber 2c of the primary pulley 2 so that a differential thrust is generated by the amount of the second thrust. The maximum hydraulic pressure may be used. As a result, the shift speed can be further increased, and the shift to the Low side can be quickly performed (effect corresponding to claim 4).

  In the present embodiment, the second oil chamber 2d is formed closer to the movable pulley 2b than the first oil chamber 2c. However, the first oil chamber may be formed closer to the movable pulley than the second oil chamber.

  In the present embodiment, the continuously variable transmission 1 is a so-called single pressure adjustment system that supplies line pressure as a secondary pressure. .

1 continuously variable transmission 2 primary pulley 2a fixed pulley 2b movable pulley 2c first oil chamber 2d second oil chamber 3 secondary pulley 3a fixed pulley 3b movable pulley 3c oil chamber (third oil chamber)
6 Controller (thrust ratio calculation means, instruction thrust ratio calculation means, hydraulic control means)
7 Oil pump (hydraulic supply means)

Claims (6)

According to a primary thrust that is a total thrust of a first thrust generated by the hydraulic pressure of the first oil chamber and a second thrust generated by the hydraulic pressure of the second oil chamber. A primary pulley that displaces the movable pulley in the axial direction of the fixed pulley;
A secondary pulley having a third oil chamber communicating with the first oil chamber, and displacing the movable pulley in the axial direction of the fixed pulley according to the secondary thrust generated by the hydraulic pressure of the third oil chamber;
And a hydraulic pressure supply means for supplying hydraulic pressure to the first oil chamber and the third oil chamber. When the hydraulic pressure is supplied to the third oil chamber, oil is supplied to the first oil chamber. A vehicle control device for controlling a vehicle including a transmission,
Thrust ratio calculation means for calculating a thrust ratio that is a value obtained by dividing the primary thrust by the secondary thrust;
An instruction thrust ratio calculating means for calculating an instruction thrust ratio for achieving a target speed ratio of the continuously variable transmission;
Hydraulic control means for controlling the hydraulic pressure supply means based on the indicated thrust ratio,
When the indicated thrust ratio is smaller than a lower limit thrust ratio set by dividing the pressure receiving area of the first oil chamber by the pressure receiving area of the third oil chamber, the hydraulic pressure control means A control apparatus for a vehicle, wherein the hydraulic pressure supply means is controlled so that a difference from a lower limit thrust ratio becomes large. The instruction thrust ratio calculation means includes:
Secondary thrust calculation means for calculating the secondary thrust for achieving the target gear ratio based on the driving state;
Primary thrust calculation means for calculating the primary thrust for achieving the target gear ratio based on the secondary thrust;
First thrust calculating means for calculating the first thrust;
Second thrust calculation means for calculating the second thrust based on the primary thrust and the first thrust,
The hydraulic pressure control means controls the hydraulic pressure supply means based on the second thrust calculated by the second thrust calculation means when the second thrust calculated by the second thrust calculation means is equal to or less than zero. The vehicle control device according to claim 1, wherein the vehicle control device controls the vehicle.   The hydraulic pressure control means controls the hydraulic pressure supply means so that the hydraulic pressure supplied to the first oil chamber and the third oil chamber is high when the vehicle is in a coasting state. Item 3. The vehicle control device according to Item 1 or 2.   4. The hydraulic control unit according to claim 1, wherein the hydraulic pressure supplied to the first oil chamber or the third oil chamber is set to a maximum hydraulic pressure in the continuously variable transmission. 5. Vehicle control device.   When the second thrust calculated by the second thrust calculation means is less than or equal to zero, the hydraulic pressure control means is equal to the secondary thrust by the amount of the second thrust calculated by the second thrust calculation means. 4. The vehicle control device according to claim 1, wherein the hydraulic pressure supply unit is controlled such that a difference from the first thrust is generated. 5. According to a primary thrust that is a total thrust of a first thrust generated by the hydraulic pressure of the first oil chamber and a second thrust generated by the hydraulic pressure of the second oil chamber. A primary pulley that displaces the movable pulley in the axial direction of the fixed pulley;
A secondary pulley having a third oil chamber communicating with the first oil chamber, and displacing the movable pulley in the axial direction of the fixed pulley according to the secondary thrust generated by the hydraulic pressure of the third oil chamber;
Hydraulic pressure supply means for supplying hydraulic pressure to the first oil chamber and the third oil chamber, and when hydraulic pressure is supplied to the third oil chamber by the hydraulic pressure supply means, oil is supplied to the first oil chamber. A vehicle control method for controlling a vehicle including a continuously variable transmission to be supplied,
Calculating a thrust ratio which is a value obtained by dividing the primary thrust by the secondary thrust;
Calculating an instruction thrust ratio that achieves a target speed ratio of the continuously variable transmission;
The difference between the thrust ratio and the lower limit thrust ratio when the indicated thrust ratio is smaller than the lower limit thrust ratio set by dividing the pressure receiving area of the first oil chamber by the pressure receiving area of the third oil chamber. A control method for a vehicle, wherein the hydraulic pressure supply means is controlled so as to increase.

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